KELLY SERVICES INC

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. )

Filed by the Registrant ☒

Filed by a party other than the Registrant ☐

Check the appropriate box:

Kelly Services Inc.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

Vision

To be the top workforce

solutions provider that drives

limitless opportunities

and growth by connecting

organizations with specialty

talent.

Letter to Shareholders

April 14, 2025

Dear Shareholders:

2024 marked a period of significant strategic progress for Kelly as we accelerated forward on our specialty growth journey. We entered the year a more efficient and focused enterprise expecting to deliver above-market results on a consistent basis. Our priorities were clear: capture a greater share of customer demand, and more effectively converttop-line growth to bottom-line profitability. Through disciplined execution and dedication to meeting the evolving needs of our clients and talent, we delivered on these commitments and are poised to drive further progress in 2025.

Capturing Market Share and Driving Organic Growth

Kelly achieved positive organic revenue growth in 2024 that outperformed the market, driven by strategic contributions from each of our business units and our organic growth initiatives. Kelly Education once again delivered double-digit revenue growth through continued strong fill rates andnet-new customer wins in its market-leading K-12 specialty. Kelly Science, Engineering & Technology (SET) maintained its focus on expanding into the market for higher-margin outcome-based offerings through its innovative statementWorx suite of solutions. Kelly Professional & Industrial (P&I) continued to capture industrial and commercial staffing market share through its omni-channel delivery strategy, and capitalized on growing demand for outcome-based solutions in semiconductors, logistics, manufacturing, and distribution. KellyOCG achieved solid revenue growth driven by its payroll process outsourcing solution while building a strong pipeline and winning a number of higher-margin managed service provider (MSP) and recruitment process outsourcing (RPO) opportunities. Across our portfolio, our large enterprise account strategy enabled our businesses to penetrate further into Kelly’s blue-chip client base.

We delivered these results notwithstanding a challenging operating environment in which total staffing industry revenues declined in most segments by double digits. Our achievements against this backdrop further reinforce our strategic decision to focus onin-demand specialties in which Kelly is well positioned to compete and win.

Significantly Improving Kelly’s Profitability

We remained laser-focused on improving profitability as well. In 2024, we delivered 100 basis points of adjusted EBITDA margin expansion, increasing our full-year EBITDA margin to 3.3% on an adjusted basis. This represents a significant increase over Kelly’s recent historical average of approximately 2.0%. Contributing to this improvement are sustained structural efficiencies and Kelly’s ongoing shift

toward higher margin, higher growth areas. This includes outcome-based solutions, which now represent more thanone-third of P&I and SET’s revenue, and an even greater portion of each business unit’s gross profit.

Redeploying Capital to Create Shareholder Value

Following the sale of Kelly’s European staffing business at the beginning of the year, we swiftly redeployed the proceeds in support of our inorganic growth strategy. In May, we completed the purchase of Motion Recruitment Partners (MRP). This transformational acquisition strengthened the scale and capabilities of Kelly’s technology staffing, consulting and RPO solutions in attractive customer end markets. The highly complementary nature of MRP’s portfolio of businesses and Kelly’s SET and OCG businesses enhance Kelly’s revenue growth potential and drive continued EBITDA margin expansion.

We also accelerated the expansion of Kelly Education’s higher-margin therapy business through the acquisition of Children’s Therapy Center (CTC), which we completed in November. Specializing in occupational, physical, and speech therapy for children, CTC brings scale to our current network of licensed therapists, enabling flexible practice in clinics or schools.

In addition to inorganic investments, we maintained our commitment to shareholder remuneration. In 2024, we returned $21 million to shareholders through dividends and share repurchases. This includes $10 million of Class A common shares repurchased under the $50 million authorization approved by Kelly’s Board of Directors in November – a reflection of our unwavering confidence in the Company’s specialty growth strategy.

A Different Kelly

We move forward in 2025 propelled by positive momentum from our recent achievements and well positioned to accelerate profitable growth when staffing demand rebounds. We are committed to deliveringtop-line growth by continuing to increase scale and capture market share in our chosen specialties. We will continue to optimize Kelly’s operating model, unlocking additional value-creating opportunities and further enhancing organizational efficiency and effectiveness. Finally, we are laser-focused on driving incremental EBITDA margin expansion. With strategic initiatives targeting both growth and efficiency, we are well positioned to delivertop- and bottom-line results that outperform the market on a consistent basis – reinforcing that this is a different Kelly.

We extend our appreciation to the members of Kelly’s Board of Directors for their guidance and commitment to the Company’s success. We are particularly appreciative of Donald Parfet, who will retire as a director at the conclusion of his current term in May. A member of the Board since 2004, Mr. Parfet’s tenure includes terms as Lead Director from 2012 to 2018, and as Chairman from 2018 to 2023. We thank him for his leadership and dedicated service to the Company.

We are grateful for your support as we move forward on our journey to unleash Kelly’s full potential. With our team focused on our specialty growth strategy and guided by our Noble Purpose, we look forward to building on our momentum and rewarding you for placing your trust in our Company.

With appreciation,

“Kelly has made significant strides on our specialty journey, and we are well positioned to capitalize on opportunities to further enhance profitability and drive growth. With our team focused on our specialty strategy and guided by our Noble Purpose, Kelly will reach new heights in 2025 and create even more value for our clients, talent, employees, and shareholders.”

Peter Quigley, President and CEO

Notice of Annual Meeting of Shareholders

2025 Annual Meeting of Shareholders

If you were a holder of record of the Company’s Class B Common Stock at the close of business on the Record Date, March 20, 2025, you are entitled to vote at the Annual Meeting.

Please promptly submit your vote by internet, telephone, or by signing, dating, and returning the enclosed proxy card or voting instructions form in the postage-paid envelope provided so that your shares will be represented and voted at the meeting.

Thank you for your interest in Kelly.

By Order of the Board of Directors,

VANESSA P. WILLIAMS

Corporate Secretary