IDEXX LABORATORIES INC /DE

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934 (Amendment No. )

IDEXX Laboratories, Inc.

(Name of Registrant as Specified in its Charter)

(Name of Person(s) Filing Proxy Statement, if Other Than the Registrant)

To Our Colleagues, Shareholders and Other Stakeholders,

In many ways, 2025 was a defining year for IDEXX. We successfully scaled multiple transformative innovations, expanded our commercial presence in key international regions and made meaningful strategic progress toward our long-term potential. With momentum from these achievements, the strength of our teams and a thoughtful, orderly upcoming planned CEO transition underway, we enter 2026 with confidence in our strategy and our ability to realize the opportunities ahead for many years to come.

2025 Financial Performance and Business Execution

During the past year, we delivered solid financial results supported by consistent, high-levels of execution. We achieved 10% reported and organic revenue growth, including 9% reported and 8% organic Companion Animal Group (CAG) Diagnostics recurring revenue growth.1 Reported diluted earnings per share (EPS) increased to $13.08 per share, resulting in 23% reported and 14% annual comparable EPS growth,2 supported by strong comparable operating margin improvements.2

We delivered these strong financial results despite a 2% decline in U.S. same-store clinical visit levels, demonstrating the resilience and durability of our business model. Notable 2025 business execution highlights include:

+More than 22,000 premium instrument placements, including over 6,000 IDEXX inVue Dx™ cellular analyzers, driving 12% growthin our premium instrument installed base.

+Double-digit installed-base growth of our ezyVet™ and Neo™ cloud-based practice management systems (PIMS), with our cloud-native PIMS surpassing 10,000 locations.

+Three international commercial expansions in Australia, Germany and the United Kingdom to support more frequent, higher‑quality interactions with clinics and support deeper integration of diagnostics into everyday care protocols, while also expanding our U.S.-based field resources.

+Customer retention in the high nineties within our key CAG Diagnostics business.

+Broad adoption of IDEXX Cancer Dx™ canine lymphoma screening tests with more than 5,500 customers in North America running the test.

Advancement of Our Innovation-Driven Strategy and Other Strategic Priorities

In 2025, we continued to invest in research and development to advance our innovation-driven strategy and build on our over 40‑year history of innovation to improve the standard of care in veterinary medicine and help our customers navigate the complexities of modern veterinary care. Select highlights include the following:

+IDEXX Cancer Dx, a first-of-its-kind diagnostic panel with early detection of canine lymphoma, was launched in the U.S. and Canada, establishing our position in early cancer detection and laying the foundation for our differentiated oncology diagnostics franchise.

+Our inVue Dx Cellular Analyzer platform was expanded toinclude fine needle aspirate (FNA) cytology, starting with mast cell tumor detection for dogs through a controlled rollout in the United States in late 2025, with broad availability expanding throughout 2026, which will empower veterinarians to evaluate skin masses, identify and quantify cells, and obtain results while pet owners are still present in-clinic.

+The Catalyst™ Cortisol Test was introduced, making it the third menu expansion in approximately a year for the Catalyst platform, addressing what was the most frequently requested Catalyst menu expansion from customers. The Catalyst Cortisol Test measures real-time quantitative cortisol concentrations in dogs and enables veterinarians to accurately diagnose or rule out Addison’s disease and Cushing’s syndrome during the patient visit, allowing for immediate treatment or adjustments to ongoing care management.

+The ImageVue™ DR50 Plus Digital Imaging System, an advanced diagnostic imaging solution for veterinary practices, underwent final development during 2025 and launched in January 2026. This system combines high-definition, AI-powered imaging at the lowest dose of radiation—reducing exposure by up to 25% compared to IDEXX’s current best-in-class ImageVue™ DR50 system and up to 60% compared to other veterinary imaging solutions—setting a new benchmark for radiation safety.

We also advanced many other critically important strategic priorities relating to customer experience, our commercial capability, performance excellence and productivity, our talent and our corporate responsibility initiatives to support long-term, sustainable value creation for our shareholders and other stakeholders. Additional details about these and our other many achievements during 2025 can be found in our 2026 Proxy Statement under “Compensation Discussion and Analysis” beginning on page 78.

“It has been a privilege to lead IDEXX since 2019, and I am confident IDEXX is well-positioned for sustained growth and success. Having worked closely with Mike for more than a decade, I know firsthand his deep knowledge of our business and believe he is the right person to lead IDEXX into the future. I look forward to continuing our work together in my role as Executive Chair to support a smooth transition and advance IDEXX’s strategic priorities.”Statement ofJonathan (Jay) Mazelsky, President and CEO

“The Board thanks Jay for his outstanding leadership and dedicated service to IDEXX. During his tenure as CEO, IDEXX advanced its innovation-driven growth strategy and expanded its offerings globally. As a result, IDEXX is poised for continued success well into the future. We look forward to continuing to work with Jay in his capacity as Executive Chair and wish him all the best in his retirement in May 2027. The Board is highly confident that Dr. Erickson is uniquely well-situated to lead IDEXX forward and continue advancing our innovation-driven strategy to create long-term value for our shareholders and other stakeholders.”Statement ofLawrence D. Kingsley, Independent Non-Executive Board Chair

As we disclosed this January, after a successful tenure as Chief Executive Officer (CEO) since 2019, Jay will step down as President and CEO effective upon the adjournment of the 2026 Annual Meeting of Shareholders on May 12, 2026, and Michael (Mike) G. Erickson, PhD, will assume the role of President and CEO. Jay will serve as Executive Chair of the Board for a one-year period until his retirement in May 2027 in order to facilitate a smooth and seamless CEO transition and provide support, advice and mentorship to Mike. Additional information about the orderly, robust and thoughtful CEO succession planning process overseen by our Board can be found under “Planned CEO Transition” on page 39.

Extending Thanks to the IDEXX Team

We extend our appreciation to all our employees around the world, whose dedication and hard work enabled us to deliver strong 2025 performance. We also wish to thank Anne Szostak, who will be retiring from the Board this May, for her many valuable contributions to our Board over her nearly 14 years of service, including as Chair of our Compensation and Talent Committee and our Governance and Corporate Responsibility Committee.

Looking Ahead

As we focus on 2026 and the future, we remain firmly committed to delivering on our Purpose: to create exceptional long-term value for our customers, employees and shareholders by enhancing the health and well-being of pets, people and livestock. We remain confident that we are well-positioned to build on our momentum and deliver diagnostic and digital tools to enhance veterinary practice productivity, improve medical outcomes, support sustainable practice growth and focus on the estimated $45+ billion total global addressable companion animal diagnostics revenue opportunity.

Thank you for your continued support of IDEXX. We look forward to joining our shareholders on May 12th at our annual meeting.

Sincerely,

1. Information regarding organic revenue growth, which is a non-GAAP (generally accepted accounting principles in the United States) financial measure, and its reconciliation to reported revenue growth, is provided in Appendix A.

2. Information regarding comparable EPS growth and comparable operating margin improvement, which are non-GAAP financial measures, and their reconciliation to reported EPS growth and operating profit margin improvement, respectively, are provided in Appendix A.

Notice of 2026 Annual Meeting

of Shareholders

NOTICE IS HEREBY GIVEN of the 2026 Annual Meeting of Shareholders (2026 Annual Meeting) of IDEXX Laboratories, Inc. We will first make available to our shareholders this Proxy Statement and the form of proxy relating to the 2026 Annual Meeting, as well as our 2025 Annual Report on Form 10‑K filed with the SEC on February 20, 2026, on or about March 27, 2026. The 2026 Annual Meeting will be held:

Shareholder Voting Matters Summary

Virtual Meeting Admission

Shareholders of record as of March 16, 2026 will be able to participate in the 2026 Annual Meeting by visitingwww.virtualshareholdermeeting.com/IDXX2026. To participate in the 2026 Annual Meeting, shareholders of record will need the control number or QR code included on their Notice of Internet Availability of the proxy materials, on their proxy card or on the instructions that accompanied their proxy materials. The annual meeting will begin promptly at 10:00 a.m., Eastern Time. Online check-in will begin at 9:30 a.m., Eastern Time, and you should allow ample time for the online check-in procedures.

In the event of a technical malfunction or other situation that the chair of the 2026 Annual Meeting determines may affect the ability of the 2026 Annual Meeting to satisfy the requirements for a meeting of shareholders to be held by means of remote communication under applicable Delaware corporate law, or that otherwise makes it advisable to adjourn the 2026 Annual Meeting, the chair or secretary of the 2026 Annual Meeting will convene the meeting at 10:00 a.m., Eastern Time, on the date specified above at One IDEXX Drive, Westbrook, Maine 04092, solely for the purpose of adjourning the meeting to reconvene at a date, time and physical or virtual location announced by the chair of the 2026 Annual Meeting. Under the foregoing circumstances, we will post information regarding the announcement on the Investor Relations section of our website (www.idexx.com).

Pre-Meeting Forum

The online format for our 2026 Annual Meeting also allows us to communicate more effectively with you through our online pre‑meeting forum, which can be accessed at www.proxyvote.com. At this online pre-meeting forum, you can submit questions in advance of our 2026 Annual Meeting, vote, view the Rules of Conduct and Procedures relating to the 2026 Annual Meeting and access copies of proxy materials and our annual report.

By order of the Board of Directors,

Sharon E. Underberg

Executive Vice President,

General Counsel and Corporate Secretary

Westbrook, Maine

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