Five9, Inc.

1. Description of Business and Summary of Significant Accounting Policies

Five9, Inc. and its wholly-owned subsidiaries (the “Company”) is a provider of cloud software for contact centers. The Company was incorporated in Delaware in 2001 and is headquartered in San Ramon, California. The Company has offices in Europe, Asia and Australia, which primarily provide research, development, sales, marketing, and customer support services.

Basis of Presentation

The accompanying condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) and applicable rules and regulations of the Securities and Exchange Commission (“SEC”) regarding interim financial reporting. Certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. Therefore, these condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024. In the opinion of management, the condensed consolidated financial statements reflect all adjustments, which are normal and recurring in nature, necessary for fair financial statement presentation. All intercompany transactions and balances have been eliminated in consolidation.

Use of Estimates

The preparation of condensed consolidated financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. The significant estimates made by management affect revenue and related reserves, as well as the fair value of assets acquired and liabilities assumed through business combinations and the fair value of performance-based restricted stock units ("PRSUs"). Management periodically evaluates such estimates and they are adjusted prospectively based upon such periodic evaluation. Actual results could differ from those estimates.

Significant Accounting Policies

There have been no material changes from the significant accounting policies previously disclosed in Part II, Item 8, of the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2024 as filed with the SEC on February 21, 2025.

Recent Accounting Pronouncements Not Yet Effective

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. This ASU requires disclosure of specific categories in the effective tax rate reconciliation and additional information on income taxes paid. This ASU is effective for the Company’s fiscal years beginning after December 15, 2024. Early adoption is permitted and may be adopted on a prospective or retrospective basis. The Company is currently evaluating the impact of this ASU on its consolidated financial statement disclosures.

In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40), and in January 2025, the FASB issued ASU 2025-01, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Clarifying the Effective Date, which clarified the effective date of ASU 2024-03. This ASU is intended to improve the decision-usefulness of expense information on public companies’ income statements through disaggregation of relevant expense captions in the notes to the financial statements. The guidance, as clarified by ASU 2025-01, is effective for annual reporting periods beginning after December 15, 2026, and interim periods within annual reporting periods beginning after December 15, 2027, with early adoption permitted. The Company is currently assessing the impact of this ASU on its consolidated financial statements and related disclosures.

In November 2024, the FASB issued ASU 2024-04, Debt with Conversion and Other Options (Subtopic 470-20), which clarifies the requirements for determining whether certain settlements of convertible debt instruments should be accounted for as an induced conversion. The ASU is effective for annual and interim reporting periods beginning after December 15, 2025. Early adoption is permitted for entities that have implemented

ASU 2020-06, with the option to apply the guidance prospectively or retrospectively. The Company is currently assessing the impact of this ASU on its consolidated financial statements.

2. Revenue

Contract Balances

The following table provides information about accounts receivable, net, deferred contract acquisition costs, net, contract assets and contract liabilities from contracts with customers (in thousands):

The Company receives payments from customers based upon billing cycles. Invoice payment terms are usually 30 days or less. Accounts receivable are recorded when the right to consideration becomes unconditional.

Deferred contract acquisition costs are recorded when incurred and are amortized over an estimated customer benefit period offive years.

The Company’s contract assets consist of unbilled amounts typically resulting from professional services where revenue is recognized in excess of total amounts billed to the customer. The Company’s contract liabilities consist of advance payments and billings in excess of revenue recognized.

In the three and six months ended June 30, 2025, the Company recognized revenue of $11.4 million and $60.9 million related to its contract liabilities at December 31, 2024.

Remaining Performance Obligations

As of June 30, 2025, the aggregate amount of the total transaction price allocated in contracts with original duration of greater than one year to the remaining performance obligations was $1,150.1 million. The Company expects to recognize revenue on approximately three-fourths of the remaining performance obligations over the next 24 months, with the balance recognized thereafter. The Company excludes amounts for remaining performance obligations that are part of contracts with an original expected duration of one year or less. Such remaining performance obligations represent unsatisfied or partially unsatisfied performance obligations.

3. Investments and Fair Value Measurements

Marketable Investments

The Company’s marketable investments have been classified and accounted for as available-for-sale. The Company’s intent is that all marketable investments are available for use in its current operations, including marketable investments with maturity dates greater than one year from June 30, 2025. The Company’s short-term marketable investments as of June 30, 2025 and December 31, 2024 were as follows (in thousands):

The following table presents the gross unrealized losses and the fair value for those marketable investments that were in an unrealized loss position for less than 12 months as of June 30, 2025 and December 31, 2024 (in thousands):

Although the Company had certain available-for-sale debt securities in an unrealized loss position as of June 30, 2025, no impairment loss was recorded since it did not intend to sell them, did not anticipate a need to sell them, and the decline in fair value was not due to any credit-related factors.

The amortized cost and fair value of the Company’s marketable investments by contractual maturity as of June 30, 2025 were as follows (in thousands):

Fair Value Measurements

The Company carries cash equivalents and marketable investments at fair value. Fair value is based on the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Fair value is estimated by applying the following hierarchy, which prioritizes the inputs used to measure fair value into three levels and bases the categorization within the hierarchy upon the lowest level of input that is available and significant to the fair value measurement:

Level 1 — Observable inputs, which include unadjusted quoted prices in active markets for identical assets or liabilities.

Level 2 — Observable inputs other than Level 1 inputs, such as quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

Level 3 — Unobservable inputs that are supported by little or no market activity and that are based on management’s assumptions, including fair value measurements determined by using pricing models, discounted cash flow methodologies or similar techniques.

The Company determined the fair value of its Level 1 financial instruments, which are traded in active markets, using quoted market prices for identical instruments.

Marketable investments classified within Level 2 of the fair value hierarchy are valued based on other observable inputs, including broker or dealer quotations or alternative pricing sources. When quoted prices in active markets for identical assets or liabilities are not available, the Company relies on non-binding quotes from its investment managers, which are based on proprietary valuation models of independent pricing services. These models generally use inputs such as observable market data, quoted market prices for similar instruments, historical pricing trends of a security as relative to its peers. To validate the fair value determination provided by its investment managers, the Company reviews the pricing movement in the context of overall market trends and trading information from its investment managers. The Company performs routine procedures such as comparing prices obtained from independent sources to ensure that appropriate fair values are recorded.

The following tables set forth the Company’s assets measured at fair value by level within the fair value hierarchy (in thousands):

In March 2024, the Company issued $747.5 million aggregate principal amount of 1.00% convertible senior notes due 2029 (the "2029 convertible senior notes") in a private offering. In connection with the issuance of the 2029 convertible senior notes, the Company used part of the net proceeds from the issuance to repurchase approximately $313.1 million aggregate principal amount of its 0.50% convertible senior notes due 2025 (the "2025 convertible senior notes"). As of December 31, 2024, the estimated fair value of the outstanding 2025 convertible senior notes was $423.2 million. The 2025 convertible senior notes matured on June 1, 2025, and the Company settled its obligations with respect to the 2025 senior notes in cash in connection therewith. As of June 30, 2025 and December 31, 2024, the estimated fair value of the outstanding 2029 convertible senior notes was $653.7 million and $674.8 million, respectively. The fair values were determined based on the quoted price of the convertible senior notes in an inactive market on the last trading day of the reporting period and have been classified as Level 2 in the fair value hierarchy. See Note 6 for further information on the Company’s convertible senior notes.

In February 2022, the Company made a $2.0 million equity investment in a privately-held company that the Company does not have the ability to exercise significant influence over. The Company elected to utilize the measurement alternative for an equity security without a readily determinable fair value. Accordingly, this investment is accounted for at its cost minus impairment, if any, and is classified within Level 3. If the Company identifies observable price changes in orderly transactions for such investment or a similar investment, it will measure the investment at fair value as of the date that the observable transactions or events occurred. During 2024, the Company noted an indicator of impairment of this investment and recorded a $1.3 million impairment charge. The Company concluded that there was no further indicator of impairment of this investment as of June 30, 2025.

Except for the equity investment described above, there wereno assets or liabilities measured at fair value on a non-recurring basis as of June 30, 2025 and December 31, 2024.

The fair value of the Company’s other financial instruments, including accounts receivable, accounts payable and other current liabilities, approximate their carrying value due to the relatively short maturity of those instruments. The carrying amounts of the Company’s operating and finance leases approximate their fair value, which is the present value of expected future cash payments based on assumptions about current interest rates and the creditworthiness of the Company.

4. Financial Statement Components

Cash and cash equivalents consisted of the following (in thousands):

Accounts receivable, net consisted of the following (in thousands):

There was one customer that represented 12% of accounts receivable as of June 30, 2025.

Prepaid expenses and other current assets consisted of the following (in thousands):

Property and equipment, net consisted of the following (in thousands):

Depreciation and amortization expense associated with property and equipment was $11.2 million and $21.6 million for the three and six months ended June 30, 2025, respectively. Depreciation and amortization expense associated with property and equipment was $10.3 million and $19.8 million for the three and six months ended June 30, 2024, respectively. During the three and six months ended June 30, 2025, the Company recorded impairment charge of property and equipment in the amount of $0.5 million and $0.8 million, respectively.

Other assets consisted of the following (in thousands):

Accrued and other current liabilities consisted of the following (in thousands):

Other long-term liabilities consisted of the following (in thousands):

5. Goodwill and Intangible Assets

The following table summarizes the activity in the Company's goodwill and intangible asset balances during the six months ended June 30, 2025 (in thousands):

The components of intangible assets were as follows (in thousands):

Amortization expense related to intangible assets was $3.5 million and $7.6 million for the three and six months ended June 30, 2025, respectively. Amortization expense related to intangible assets was $2.6 million and $5.3 million for the three and six months ended June 30, 2024, respectively.

As of June 30, 2025, the expected future amortization expense for intangible assets was as follows (in thousands):

6. Debt

Repurchase Transaction

In connection with the issuance of the 2029 convertible senior notes on March 1, 2024, the Company used part of the net proceeds from the issuance to repurchase approximately $313.1 million aggregate principal amount of the outstanding 2025 convertible senior notes in privately-negotiated transactions for aggregate cash consideration of approximately $304.9 million (the “Repurchase Transaction”).

The Repurchase Transaction was accounted for as a debt extinguishment. The difference between the consideration used to extinguish the 2025 convertible senior notes and the carrying value of the 2025 convertible senior notes (including unamortized debt discount and issuance costs) resulted in an extinguishment gain of approximately $6.6 million recorded in Other income (expense), net on the Company’s condensed consolidated statements of operations and comprehensive income (loss).

In connection with the Repurchase Transaction, the Company also entered into a partial termination agreement with each bank counterparty and unwound a corresponding portion of the previously purchased capped call instruments entered into in connection with the issuance of the 2025 convertible senior notes (the “2025 Capped Calls”). The Company received approximately $0.5 million in cash in connection with these partial terminations, representing the fair value at the date of settlement of the unwound 2025 Capped Calls.

2029 Convertible Senior Notes and Related Capped Call Transactions

In March 2024, the Company issued $747.5 million aggregate principal amount of 2029 convertible senior notes in a private offering, which aggregate principal amount included the exercise in full of the initial purchasers’ option to purchase up to an additional $97.5 million principal amount of the 2029 convertible senior notes. The 2029 convertible senior notes mature on March 15, 2029 and bear interest at a fixed rate of 1.00% per annum, payable semiannually in arrears on March 15 and September 15 of each year, beginning on September 15, 2024. The total net proceeds from the issuance of the 2029 convertible senior notes, after deducting initial purchasers' discounts and commissions and estimated debt issuance costs, were approximately $728.8 million.

Each $1,000 principal amount of the 2029 convertible senior notes is initially convertible into 12.5918 shares of the Company’s common stock (the “2029 Conversion Option”), which is equivalent to an initial conversion price of approximately $79.42 per share of common stock, subject to adjustment upon the occurrence of specified events. The initial conversion price represents a premium of approximately 30% to the $61.09 per share closing price of the Company’s common stock on The Nasdaq Global Market on February 27, 2024. There have been no changes to the initial conversion price of the 2029 convertible senior notes since issuance. The 2029 convertible senior notes are convertible, in multiples of $1,000 principal amount, at the option of the holders prior to the close of business on the business day immediately preceding December 15, 2028, only under the following circumstances: (1) during any calendar quarter commencing after the calendar quarter ending on June 30, 2024 (and only during such calendar quarter), if the last reported sale price of the Company’s common stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the conversion price on each applicable trading day; (2) during thefive business day period after anyfive consecutive trading day period (the “2029 Measurement Period”) in which the trading price (as defined in the 2029 Indenture governing the 2029 convertible senior notes) per $1,000 principal amount of the 2029 convertible senior notes for each trading day of the 2029 Measurement Period was less than 98% of the product of the last reported sale price of the Company’s common stock and the conversion rate in effect on each such trading day; (3) if the Company calls any or all of the 2029 convertible senior notes for redemption, at any time prior to the close of business on the second scheduled trading day immediately preceding the redemption date; or (4) upon the occurrence of specified corporate events. On or after December 15, 2028 until the close of business on the second scheduled trading day immediately preceding the maturity date, holders may convert all or any portion of their 2029 convertible senior notes, in multiples of $1,000 principal amount, at the option of the holder regardless of the foregoing circumstances.

Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of the Company’s common stock or a combination of cash and shares of the Company’s common stock, at the Company’s election. If the Company undergoes a fundamental change (as defined in the indenture governing the 2029 convertible senior notes), subject to certain conditions, holders may require the Company to repurchase for cash all or any portion of their 2029 convertible senior notes, in principal amounts of $1,000 or a multiple thereof, at a fundamental change repurchase price equal to 100% of the principal amount of the 2029 convertible senior notes to be repurchased, plus accrued and unpaid interest, if any, to, but excluding, the fundamental change repurchase date. In addition, following certain corporate events or if the Company issues a notice of redemption, it will, under certain circumstances, increase the conversion rate for holders who elect to convert their notes in connection with such corporate event or during the relevant redemption period.

The closing market price of the Company's common stock of $26.48 per share on June 30, 2025, the last trading day during the three months ended June 30, 2025, was below $103.24 per share, which represents 130% of the initial conversion price of $79.42 per share. Additionally, the last reported sale price of the Company’s common stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on, and including, the last trading day, June 30, 2025, was not greater than or equal to 130% of the initial conversion price. As such, during the three months ended June 30, 2025, the conditions allowing holders of the 2029 convertible senior notes to convert were not met. The 2029 convertible senior notes are therefore not convertible during the three months ending September 30, 2025.

The Company may not redeem the 2029 convertible senior notes prior to March 22, 2027. The Company may redeem for cash all or any portion of the 2029 convertible senior notes, at its option, on or after March 22, 2027 and prior to December 15, 2028, if the last reported sale price of its common stock has been at least 130% of the conversion price then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading day period (including the last trading day of such period) ending on, and including, the trading day immediately preceding the date on which the Company provides notice of redemption at a redemption price equal to 100% of the principal amount of the 2029 convertible senior notes to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption date. However, the Company may not redeem less than all of the outstanding 2029 convertible senior notes unless at least $100.0 million aggregate principal amount of 2029 convertible senior notes are outstanding and not called for redemption at the time the redemption notice is sent. No sinking fund is provided for the 2029 convertible senior notes.

The 2029 convertible senior notes are the Company’s senior unsecured obligations and rank senior in right of payment to any of the Company’s indebtedness that is expressly subordinated in right of payment to the 2029 convertible senior notes; equal in right of payment to any of the Company’s unsecured indebtedness that is not so subordinated (including the 2025 convertible senior notes); effectively junior in right of payment to any of the Company’s secured indebtedness to the extent of the value of the assets securing such indebtedness; and structurally junior to all indebtedness and other liabilities.

The net carrying amount of the 2029 convertible senior notes was as follows (in thousands):

Interest expense related to the 2029 convertible senior notes was as follows (in thousands):

The debt issuance costs are amortized into interest expense over the term of the 2029 convertible senior notes at an effective interest rate of 1.49%.

In connection with the issuance of the 2029 convertible senior notes, the Company entered into privately negotiated capped call transactions (each a “2029 Capped Call,” and collectively the "2029 Capped Calls") with certain financial institutions. The 2029 Capped Call has an initial strike price of approximately $79.42, subject to certain adjustments, which corresponds to the initial conversion price of the 2029 convertible senior notes. The 2029 Capped Calls have an initial cap price of $122.18 per share, subject to certain adjustments. The 2029 Capped Calls are expected to partially offset the potential dilution to the Company’s common stock upon any conversion of the 2029 convertible senior notes, with such offset subject to a cap based on the cap price. Each 2029 Capped Call covers, subject to anti-dilution adjustments, approximately 9.4 million shares of the Company’s common stock. The 2029 Capped Call is subject to adjustment upon the occurrence of specified extraordinary events affecting the Company, including merger events, tender offers, and announcement events. In addition, each 2029 Capped Call is subject to certain specified additional disruption events that may give rise to a termination of the 2029 Capped Calls, including nationalization, insolvency or delisting, changes in law, failures to deliver, insolvency filings, and hedging disruptions. For accounting purposes, each 2029 Capped Call is treated as a separate transaction from, and not part of the terms of the 2029 convertible senior notes. As these transactions meet certain accounting criteria, the 2029 Capped Calls are recorded in stockholders' equity and are not accounted for as derivatives. The 2029 Capped Calls will not be remeasured as long as they continue to meet the conditions for equity classification.

2025 Convertible Senior Notes and Related Capped Call Transactions

In May and June 2020, the Company issued $747.5 million aggregate principal amount of 2025 convertible senior notes in a private offering, which aggregate principal amount included the exercise in full of the initial purchasers’ option to purchase up to an additional $97.5 million principal amount of the 2025 convertible senior notes. The total net proceeds from the issuance of the 2025 convertible senior notes, after deducting initial purchasers' discounts and commissions and estimated debt issuance costs, were approximately $728.8 million.

In March 2024, the Company used part of the net proceeds from the issuance of the 2029 convertible senior notes to repurchase $313.1 million aggregate principal amount of the 2025 convertible senior notes in privately-negotiated transactions.

The 2025 convertible senior notes matured on June 1, 2025, and the Company settled its obligations with respect to the 2025 senior notes in cash in connection therewith. Prior to maturity, the 2025 convertible senior notes bore interest at a fixed rate of 0.500% per annum, payable semiannually in arrears on June 1 and December 1 of each year. There were no changes to the 2025 convertible senior notes' initial conversion price of approximately $134.34 per share of common stock since the date of issuance.

The net carrying amount of the 2025 convertible senior notes as of December 31, 2024 was $433.5 million. There were no 2025 convertible senior notes outstanding as of June 30, 2025.

Interest expense related to the 2025 convertible senior notes was as follows (in thousands):

In connection with the issuance of the 2025 convertible senior notes, the Company entered into privately negotiated capped call transactions (each a “2025 Capped Call,” and collectively the "2025 Capped Calls") with certain financial institutions. The 2025 Capped Calls each had an initial strike price of approximately $134.34, which corresponded to the initial conversion price of the 2025 convertible senior notes. In connection with the Repurchase Transaction, the Company unwound a portion of the 2025 Capped Calls. Refer to the Repurchase Transaction section above for further information. The remaining 2025 Capped Calls covered, subject to anti-dilution adjustments, approximately 3.2 million shares of the Company’s common stock. For accounting purposes, each 2025 Capped Call was a separate transaction from, and not part of the terms of the 2025 convertible senior notes. As these transactions met certain accounting criteria, the 2025 Capped Calls were recorded in stockholders' equity and were not accounted for as derivatives. Upon maturity, the outstanding 2025 Capped Calls associated with the 2025 convertible senior notes were settled with no consideration received since their strike prices were in excess of the Company's stock price at that time.

7. Stockholders’ Equity

Capital Structure

Common Stock

The Company is authorized to issue 450,000,000 shares of common stock with a par value of $0.001 per share. As of June 30, 2025 and December 31, 2024, the Company had 77,262,690 and 75,807,505 shares of common stock issued and outstanding, respectively.

Preferred Stock

The Company is authorized to designate and issue up to 5,000,000 shares of preferred stock with a par value of $0.001 per share in one or more series without stockholder approval and to fix the rights, preferences, privileges and restrictions thereof. As of June 30, 2025 and December 31, 2024, there wereno shares of preferred stock issued and outstanding.

Common Stock Reserved for Future Issuance

Shares of common stock reserved for future issuance related to outstanding equity awards and employee equity incentive plans as of June 30, 2025 were as follows (in thousands):

Stock Options

A summary of the Company’s stock option activity during the six months ended June 30, 2025 is as follows (in thousands, except per share data):

The aggregate intrinsic value amounts are computed based on the difference between the exercise price of the stock options and the fair market value of the Company’s common stock of $26.48 per share as of June 30, 2025 for all in-the-money stock options outstanding.

Restricted Stock Units (including PRSUs)

A summary of the Company’s restricted stock unit ("RSU") activity, including PRSUs, during the six months ended June 30, 2025 is as follows (in thousands, except per share data):

(1) Includes 267,711 PRSUs granted during the six months ended June 30, 2025.

PRSUs with Market Conditions During the six months ended June 30, 2025, the Company granted 267,711 market-based PRSUs with a grant date fair value of $13.9 million. The amount that may be earned pursuant to the market-based PRSUs ranges from 0% to 200% of the target number based on the Company’s relative total shareholder return (“RTSR”) performance during the 2025-2027 performance period as compared to the performance during such period of companies in the S&P Software and Services Select Index on January 1, 2025. The 2025-2027 performance period contains three overlapping measurement periods—a one-year period (2025), a two-year period (2025–2026), and a three-year period (2025–2027). One-third of the total market-based PRSUs may be earned and settled in shares following the end of each measurement period based on RTSR performance and subject to continued employment through the payment date. If the Company’s absolute total shareholder return for any measurement period is negative, then no more than 100% of the target amount of market-based PRSUs for such period may be earned. If an executive's employment with the Company terminates before the end of the finalone-year performance period due to death or disability,100% (if due to death) or 50% (if due to disability) of the unvested market-based PRSUs may be earned subject to ultimate RTSR performance in each remaining performance period. Upon a qualifying termination of employment in connection with a change in control of the Company, the unvested market-based PRSUs subject to the 2023-2025 performance period, the 2024-2026 performance period and the 2025-2027 performance period will vest on a double-trigger basis (i) at the target level for the uncompleted portions of the performance periods and (ii) at the actual level of performance measured through the date of the change in control of the Company, based on the price per share paid in such change in control. The fair value of the market-based PRSUs is determined on their grant date using a Monte Carlo Simulation model based upon assumptions presented below. The Company recognizes the fair value of the market-based PRSUs ratably over their requisite service period.

During the first quarter of 2025, the Company certified the performance results for the 2024 measurement period for the market-based PRSUs subject to the 2022-2024 performance period, the 2023-2025 performance period and the 2024-2026 performance period. The Company determined that its actual total shareholder return was (47.25)% for 2024. The Company's relative total shareholder return ranking for the market-based PRSUs subject to the 2022-2024 performance period was in the 3.7 percentile relative to companies in the S&P Software & Services Select Index on January 1, 2022, which resulted in a payout percentage of 0.00% of target for the 2024 measurement for such PRSUs. The Company's relative total shareholder return ranking for the market-based PRSUs subject to the 2023-2025 performance period was in the 2.9 percentile relative to companies in the S&P Software & Services Select Index on January 1, 2023, which resulted in a payout percentage of 0.00% of target for the 2024 measurement period for such PRSUs. The Company's relative total shareholder return ranking for the market-based PRSUs subject to the 2024-2026 performance period was in the 1.5 percentile relative to companies in the S&P Software & Services Select Index on January 1, 2024, which resulted in a payout percentage of 0.00% of target for the 2024 measurement period for such PRSUs.

Stock-Based Compensation

Stock-based compensation expense was as follows (in thousands):

As of June 30, 2025, unrecognized stock-based compensation expense by award type and expected weighted-average recognition periods are summarized in the following table (in thousands, except years).

The weighted-average assumptions used to value PRSUs with market conditions granted during the periods presented were as follows:

(1)The Company has not paid, and does not anticipate paying, cash dividends on its shares of common stock. Accordingly, the expected dividend yield iszero.

8. Net Income (Loss) Per Share

Basic net income (loss) per share is calculated by dividing net income (loss) by the weighted average number of shares of common stock outstanding during the period, and excludes any dilutive effects of employee stock-based awards and potential shares upon conversion of the convertible senior notes. Diluted net income (loss) per share is computed giving effect to all potentially dilutive shares of common stock, including common stock issuable upon exercise of stock options, vesting of RSUs and PRSUs, and shares of common stock issuable upon conversion of convertible senior notes.

The following table presents the calculation of basic and diluted net income (loss) per share (in thousands, except per share data):

The following securities were excluded from the calculation of diluted net income (loss) per share because their effect would have been anti-dilutive (in thousands):

The Company used the if-converted method for calculating any potential dilutive effect of its convertible senior notes for the three and six months ended June 30, 2025 and 2024. Under this method, the Company calculates diluted earnings per share under both the cash and share settlement assumptions to determine which is more dilutive. If share settlement is more dilutive, the Company calculates diluted earnings per share assuming that all of the convertible senior notes were converted solely into shares of common stock at the beginning of the reporting period. The potential impact upon the conversion of the convertible senior notes were included in the calculation of diluted net income per share for the three and six months ended June 30, 2025 and were excluded in the calculation of diluted net loss per share for the three and six months ended June 30, 2024 because the effect would have been anti-dilutive.

9. Income Taxes

The provision for income taxes for the three and six months ended June 30, 2025 was approximately $1.4 million and $1.6 million, respectively. The provision for income taxes for the three and six months ended June 30, 2024 was approximately $3.3 million and $4.3 million, respectively.

The provision for income taxes for the three and six months ended June 30, 2025 and June 30, 2024 consisted primarily of U.S. federal and U.S. state tax expense as a result of IRC Section 174 research and experimental capitalization requirements and tax attribute utilization limitations, and foreign current income tax expense as a result of income produced by the Company's intercompany cost-plus operating model. For the three and six months ended June 30, 2025, the provision for income taxes differed from the statutory amount primarily due to the U.S. valuation allowance maintained against the U.S. net deferred tax assets. For the three and six months ended June 30,

2024, the provision for income taxes differed from the statutory amount primarily due to certain U.S. and foreign jurisdictions where a full valuation allowance was maintained against the net deferred tax assets.

The realization of tax benefits from deferred tax assets is dependent upon future levels of taxable income, of an appropriate character, to be recognized in the periods the items are expected to be deductible or taxable. Based on the weight of the available objective evidence, the Company does not believe it is more likely than not that the U.S. net deferred tax assets will be realizable. Accordingly, the Company has provided a full valuation allowance against such net deferred tax assets as of June 30, 2025 and December 31, 2024. The Company intends to maintain the valuation allowance until sufficient positive evidence exists to support a reversal of, or decrease in, the valuation allowance. During the three and six months ended June 30, 2025, there were no material changes to the total amount of unrecognized tax benefits.

10. Commitments and Contingencies

Commitments

The Company’s principal commitments consist of future payment obligations under its convertible senior notes, finance leases to finance data centers and other computer and networking equipment, operating leases for office facilities, cloud services and software and maintenance agreements, and agreements with third parties to provide co-location hosting and telecommunication services. These commitments as of December 31, 2024 are disclosed in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024, and material updates to these commitments during the six months ended June 30, 2025 are disclosed herein, including in this Note 10 and in Note 12.

As of June 30, 2025, the Company’s commitments under various co-location hosting and telecommunication usage service agreements totaled $12.0 million for terms ranging up to approximately five years. These agreements require the Company to make payments over the service term in exchange for certain network services.

As of June 30, 2025, the Company had outstanding cloud services and software and maintenance agreement commitments totaling $25.5 million, of which $7.4 million is expected to be purchased in the remainder of 2025, and the remaining $18.1 million is expected to be purchased in 2026. The Company entered into equipment finance lease arrangements that resulted in a $6.7 million additional reduction of its outstanding cloud services commitment. See Note 12 for more information.

As of June 30, 2025, (i) no 2025 convertible senior notes were outstanding since they matured on June 1, 2025 and the Company settled its obligations with respect to the 2025 senior notes in cash in connection therewith, and (ii) $747.5 million of aggregate principal of the 2029 convertible senior notes was outstanding, which 2029 convertible senior notes have a maturity date of March 15, 2029. See Note 6 for more information concerning the convertible senior notes.

Legal Matters

The Company is involved in various legal and regulatory matters arising in the normal course of business. In management’s opinion, resolution of these matters is not expected to have a material impact on the Company’s consolidated results of operations, cash flows, or its financial position. However, due to the uncertain nature of legal matters, an unfavorable resolution of a matter could materially affect the Company’s future consolidated results of operations, cash flows or financial position in a particular period. The Company expenses legal fees as incurred. The Company is currently party to the following action:

On December 4, 2024, a purported holder of the Company’s securities filed a putative class action complaint against the Company, its Chief Executive Officer, and its Chief Financial Officer in the United States District Court for the Northern District of California alleging violations of Section 10(b) and 20(a) of the Securities Exchange Act of 1934 and Rule 10b-5, promulgated thereunder, based on alleged false and/or misleading statements or omissions regarding the Company and its business and seeking unspecified damages on behalf of all persons and entities (subject to specified exceptions) that purchased or otherwise acquired the Company’s securities, including call options, from June 4, 2024, through the close of trading on August 8, 2024. On February 3, 2025, Lucid Alternative Fund, LP moved to be appointed lead plaintiff of this action pursuant to the Private Securities Litigation Reform Act of 1995. On March 18, 2025, the court appointed Lucid Alternative Fund, LP as lead plaintiff and approved lead plaintiff’s selection of lead counsel. Per the court’s subsequent order on March 27, 2025, Lucid Alternative Fund, LP filed an amended complaint on May 30, 2025. The Company filed a motion to dismiss the amended complaint on July 29, 2025. The Company cannot predict the duration or outcome of this lawsuit at this time. As a result, the

Company is unable to estimate the reasonably possible loss or range of reasonably possible losses arising from this lawsuit. The Company intends to vigorously defend this lawsuit.

On March 18, 2025, a related shareholder derivative action was filed in the United States District Court for the Northern District of California on behalf of nominal defendant Five9, Inc. and against its directors and certain of its officers seeking to assert claims for breach of fiduciary duty, unjust enrichment, abuse of control, gross mismanagement, and waste of corporate assets, and for contribution under Sections 10(b) and 21D of the Securities Exchange Act of 1934. The Company was served with the complaint on March 20, 2025. On April 4, 2025, the parties to the derivative action jointly filed a stipulation with the court to stay the derivative action until the resolution of the motion to dismiss in the securities action, as well as any subsequent motion to dismiss any further amended complaint in the securities action. On April 8, 2025, the court approved the stay stipulation.

Indemnification Agreements

In the ordinary course of business, the Company enters into agreements of varying scope and terms pursuant to which it agrees to indemnify customers, vendors, lessors, business partners and other parties with respect to certain matters, including losses arising out of breach of such agreements, including breach of security, services to be provided by the Company or from intellectual property infringement claims made by third parties. The Company has received indemnification demands, and will likely continue to receive demands, from customers regarding its intellectual property indemnification obligations under these contracts. In addition, the Company has entered into indemnification agreements with its directors, officers and certain employees that requires it, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors, officers or employees. There are no claims that the Company is aware of that could have a material effect on the consolidated balance sheets, consolidated statements of operations and comprehensive income (loss), or consolidated statements of cash flows.

11. Segment and Geographical Information

The Company has a single operating and reportable segment and manages its business activities on a consolidated basis. The Company’s single segment provides its solution through a SaaS business model. The Company generates subscription revenue from its Intelligent CX Platform, and also generates usage-based telephony revenue. The Company charges its customers monthly subscription fees for access to its solution, primarily based on the number of licenses. The Company’s AI solutions are sold to its customers on a consumption or capacity basis. The Company’s reliable, secure, and scalable Intelligent CX Platform, powered by Five9 Genius AI, delivers a comprehensive suite of easy-to-use applications that enable the breadth of customer service, sales, and marketing related functions. The Company’s chief operating decision maker (“CODM”) is its chief executive officer. The Company’s CODM reviews financial information presented on a consolidated basis for purposes of assessing financial performance and making operating decisions on how to allocate resources based on net income (loss) that is also reported on its consolidated statements of operations and comprehensive income (loss) as consolidated net income (loss). The measure of segment assets is reported on its consolidated balance sheets as total consolidated assets.

Revenue by Geographic Areas

The following table summarizes revenues by geographic region based on customer billing address (in thousands):

Long-Lived Assets, Net by Geographic Areas

The following table summarizes total property and equipment, net in the respective locations (in thousands):

Total purchases of property and equipment for the six months ended June 30, 2025 and 2024 are disclosed in the Company’s Consolidated Statements of Cash Flows.

Segment Information - Consolidated Statement of Operations

(1) Adjusted cost of revenue includes cost of revenue in accordance with GAAP, adjusted for depreciation and amortization, stock-based compensation, acquisition and related transaction costs and one-time integration costs, lease amortization for finance leases, and costs related to a reduction in force plan.

(2) Adjusted research and development includes research and development in accordance with GAAP, adjusted for depreciation and amortization, stock-based compensation, exit costs related to the closure and relocation of the Company’s Russian operations, acquisition and related transaction costs and one-time integration costs, lease amortization for finance leases, and costs related to a reduction in force plan.

(3) Adjusted sales and marketing includes sales and marketing expense in accordance with GAAP, adjusted for depreciation and amortization, stock-based compensation, and costs related to a reduction in force plan.

(4) Adjusted general and administrative included general and administrative expense in accordance with GAAP, adjusted for depreciation and amortization, stock-based compensation, exit costs related to the closure and relocation of the Company’s Russian operations, acquisition and related transaction costs and one-time integration costs, one-time expenses related to strategic consulting services for operational review, other cost-reduction and productivity initiatives, legal fees related to the securities class action, costs related to a reduction in force plan, and office closure lease termination costs.

(5)Other segment items included in segment net income (loss) includes stock-based compensation, exit costs related to the closure and relocation of our Russian operations, acquisition and related transaction costs and one-time integration costs, lease amortization for finance leases, one-time expenses related to strategic consulting services for operational review, other cost-reduction and productivity initiatives, legal fees related to the securities class action, costs related to a reduction in force plan, and office closure lease termination costs.

12. Leases

The Company has leases for offices, data centers and computer and networking equipment that expire at various dates through 2031. The Company’s leases have remaining terms ofone toseven years, some of the leases include a Company option to extend the leases for up toone tofive years, and some of the leases include the option to terminate the leases upon 30-days' notice. The Company does not separate lease and non-lease components for real estate operating leases.

As the Company’s leases do not provide an implicit rate, the net present value of future minimum lease payments is determined using the Company’s incremental borrowing rate. Operating leases with a duration of 12 months or less are excluded from right-of-use assets and operating lease liabilities, and related lease payments are generally recognized on a straight-line basis over the lease term and variable lease payments are recognized as incurred.

The Company entered into additional three-year equipment finance lease agreements and recognized $3.9 million right of use assets during the six months ended June 30, 2025, which were reported within Finance lease right-of-use assets and are being depreciated on a straight-line basis over the lease term. As a result, the Company also recognized short-term lease liabilities of $1.3 million within Finance lease liabilities and long-term lease liabilities of $2.6 million within Finance lease liabilities - less current portion during these periods.

The components of lease expenses were as follows (in thousands):

Supplemental cash flow information related to leases was as follows (in thousands):

Supplemental balance sheet information related to leases was as follows (in thousands):

Weighted average remaining terms were as follows (in years):

Weighted average discount rates were as follows:

Maturities of lease liabilities were as follows (in thousands):

As of June 30, 2025, the Company had entered into an additional operating lease that commenced on July 1, 2025, representing a total commitment over its term of approximately $3.8 million.

13. Acquisition

Acqueon

On August 27, 2024, the Company acquired all of the issued and outstanding shares of capital stock of Acqueon for total consideration of approximately $173.8 million. This acquisition, which was accounted for as a business combination, is intended to build on the pre-existing partnership between the companies, and to extend the Company's AI-powered CX platform by adding omnichannel proactive customer engagement to expand the Company's outbound capabilities.

The excess of the purchase price over identifiable intangible assets and net tangible assets in the amount of $139.4 million was allocated to goodwill, which is not deductible for tax purposes. The fair values assigned to assets acquired and liabilities assumed are based on management’s best estimates and assumptions as of the acquisition date and are considered preliminary pending finalization of valuation analyses pertaining to intangible assets acquired, liabilities assumed and tax liabilities assumed. During the measurement period, which may be up to one year from the acquisition date, the Company may record adjustments to the fair value of these tangible and intangible assets acquired and liabilities assumed, with the corresponding offset to goodwill. The Company recorded adjustments of less than $0.1 million and $1.3 million within the one year from acquisition date measurement period for 2024 and for the six months ended June 30, 2025, respectively.

The following table presents the preliminary allocation of the purchase price at the acquisition date (in thousands):

The acquired technology, customer relationships, and trademarks will be amortized on a straight-line basis over their estimated useful lives ofeight years, five years, andthree years, respectively. The Company used the income approach to estimate the fair value of intangible assets acquired.

In connection with this acquisition, the Company incurred total acquisition-related transaction costs of $7.9 million during 2024, and incurredno additional costs during the six months ended June 30, 2025, that have been expensed as incurred and included in general and administrative expenses in the consolidated statements of operations and comprehensive income (loss).

The results of operations of this acquisition are included in the accompanying consolidated statements of operations and comprehensive income (loss) from the date of acquisition and are not material to the Company's condensed consolidated financial statements.

14. Restructurings

On August 20, 2024, the Company announced a reduction in force plan (the “2024 Plan”) as part of its broader efforts to drive balanced, profitable growth, further supporting its positive, long-term outlook and focus on increasing stockholder value. The 2024 Plan reduced the Company’s global full-time employees by approximately 6%. For the year ended December 31, 2024, the Company incurred a total of $9.6 million in restructuring costs under the 2024 Plan, primarily consisting of notice period payments, severance payments, employee benefits and related costs, all of which are cash expenditures, of which $2.1 million was recorded in cost of revenue, $1.9 million was recorded in research and development expenses, $4.4 million was recorded in sales and marketing expenses, and $1.2 million was recorded in general and administrative expenses on the consolidated statements of operations and comprehensive income (loss). As of June 30, 2025, $9.4 million had been paid and the remaining $0.2 million was recorded within Accrued and other current liabilities in the consolidated balance sheets and is expected to be mostly paid in the second half of 2025. Other than as set forth herein, the Company doesnot expect to incur any additional costs under the 2024 Plan.

On March 31, 2025, the Board of Directors of the Company approved a reduction in force plan (the “2025 Plan”) as part of its broader efforts to prioritize investments in key strategic areas, including artificial intelligence, as well as to drive profitable growth in supporting its positive, long-term outlook and increasing stockholder value. On April 3, 2025, the Company commenced execution of the 2025 Plan, which resulted in the reduction of the Company’s global full-time employees by approximately 4%. During the three and six months ended June 30, 2025, the Company incurred a total of $7.8 million in restructuring costs under the 2025 Plan, primarily consisting of notice period payments, severance payments, employee benefits and related costs, all of which are cash expenditures, of which $1.6 million was recorded in cost of revenue, $1.9 million was recorded in research and development expenses, $3.3 million was recorded in sales and marketing expenses, and $1.0 million was recorded in general and administrative expenses on the consolidated statements of operations and comprehensive income (loss). As of June 30, 2025, $7.5 million had been paid and the remaining $0.3 million was recorded within Accrued and other current liabilities in the consolidated balance sheets and is expected to be mostly paid in the second half of 2025. During the three and six months ended June 30, 2025, the Company also incurred an additional $2.1 million in stock-based compensation costs related to the 2025 Plan due to additional vesting of share-based awards, of which $0.3 million was recorded in cost of revenue, $0.5 million was recorded in research and development expenses, $1.1 million was recorded in sales and marketing expenses, and $0.2 million was recorded in general and administrative expenses on the consolidated statements of operations and comprehensive income (loss). Other than as set forth herein, the Company does not expect to incur any additional costs under the 2025 Plan.

15. Subsequent Event

H.R.1, the One Big Beautiful Bill Act, was signed into law on July 4, 2025 (the “OBBBA”), introducing significant changes to the U.S. tax code, including the reinstatement of 100% bonus depreciation, the immediate expensing of domestic research and development expenditures under Section 174A, and modifications to the Section 163(j) interest deduction limitation, which may impact the Company's effective tax rate beginning in the third quarter of 2025. As the enactment occurred after the end of the Company's second fiscal quarter, the effects of the OBBBA are not reflected in its Q2 financial statements. However, the Company is currently evaluating the anticipated impact of the legislation on its tax position, cash flows, and capital allocation strategy.