NLIGHT, 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

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NLIGHT, INC.

(Name of Registrant as Specified In Its Charter)

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

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2026 Annual Meeting

Proxy Statement and Notice of Annual Meeting

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To Be Held at 9:00 a.m. Pacific Time on Friday, June 5, 2026

Dear Stockholders of nLIGHT, Inc.:

We cordially invite you to attend the 2026 annual meeting of stockholders (the “Annual Meeting”) of nLIGHT, Inc., a Delaware corporation, which will be held on Friday, June 5, 2026, at 9:00 a.m. Pacific Time. This year’s Annual Meeting will be a completely virtual meeting of stockholders. You can attend the Annual Meeting by visiting www.virtualshareholdermeeting.com/LASR2026 where you will be able to listen to the meeting live, submit questions and vote online. We are holding the Annual Meeting for the following purposes, as more fully described in the accompanying proxy statement:

1. To elect the Class II director nominee named in the accompanying proxy statement to serve until the 2029 annual meeting of stockholders and until his respective successor is duly elected and qualified;

2. To ratify the appointment of KPMG LLP as our independent registered public accounting firm for our fiscal year ending December 31, 2026;

3. To approve, on an advisory, non-binding basis, the compensation of our named executive officers; and

4. To transact such other business that may properly come before the Annual Meeting or any adjournments or postponements thereof.

Our board of directors has fixed the close of business on April 6, 2026, as the record date for the Annual Meeting. Only stockholders of record on April 6, 2026, are entitled to notice of and to vote at the Annual Meeting. Further information regarding voting rights and the matters to be voted upon is presented in the accompanying proxy statement.

Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting to Be Held on Friday, June 5, 2026. On or about April 24, 2026, we expect to mail to our stockholders a Notice of Internet Availability of Proxy Materials (the “Notice”) containing instructions on how to access our proxy statement and annual report. The Notice provides instructions on how to vote via the Internet, telephone or mail (if you receive printed proxy materials) and includes instructions on how to receive a paper copy of our proxy materials. The accompanying proxy statement and our annual report can be accessed directly at the following Internet address: www.proxyvote.com. All you have to do is enter the control number located on your Notice or proxy card.

YOUR VOTE IS IMPORTANT. Whether or not you plan to attend the Annual Meeting, we urge you to submit your vote via the Internet, telephone or mail as soon as possible. We appreciate your continued support of nLIGHT.

By order of the Board of Directors,

President and Chief Executive Officer

Camas, Washington

April 24, 2026

To Our Stockholders,

Twenty-five years ago, we founded nLIGHT with the vision that semiconductor lasers would improve at a rapid rate and enable important new applications. We have worked relentlessly and deliberately to expand our vertically integrated U.S. based manufacturing to support our vision and today we are stronger than ever across our technology stack from leading semiconductor laser devices to our record 300 kilowatt coherently beam combined laser. Our vision remains the same and our mission has never been more consequential.

Looking Back |Strong Growth and Expanding Leverage in 2025

We reported exceptional financial results in 2025 with full‑year revenue of $261 million, an increase of 32% year‑over‑year. Record aerospace and defense revenue of $175 million grew 60% year‑over‑year, driven by strong execution on existing programs, successful production ramps, and new contract awards that provide clear visibility into continued growth.

Our accelerated top‑line growth also drove significant improvements in bottom‑line performance. In 2025, gross margins expanded to 30%, up from 17% in 2024; and operating cash flow increased to $21 million, up from negative $2.4 million in 2024. These results demonstrate the operating leverage inherent in our model as scale increases.

Our Mission |Vertically integrated technology focused on national security

Our results in 2025 not only validated our long-standing vision but also provided heightened importance to our mission: ensuring that our vertically integrated U.S. based technology stack is aligned to support the critical technologies essential to national security in a more contested world.

We are in the midst of a multi-generational shift. The post–Cold War order that shaped global commerce, security, and innovation is giving way to sustained great-power competition and the weaponization of technology. We can no longer rely on legacy technologies alone. We are investing across every layer of our technology stack to deliver operational capability in next‑generation high‑power lasers to the United States and its allies.

Our Strategy |focus on three critical technology areas

The U.S. government’s list of critical technology areas provides clear reinforcement of our mission and focus. Within that framework, we are concentrated on three areas where our vertically integrated technology stack is meaningfully differentiated:

1. Directed Energy

nLIGHT is uniquely positioned for directed energy lasers through more than two decades of investment in industry‑leading, vertically integrated high‑power laser technology. Our capabilities span the full stack—from chips and components to coherent beam‑combined lasers and complete laser weapon modules, including beam directors and atmospheric correction. We believe that scaling output to hundreds of kilowatts using coherent‑combined architectures with fast adaptive wavefront control is essential to provide effective defensive capability against advanced threats. In 2025, we made significant progress integrating and testing a 50 kW laser weapon module for the Army’s DE M‑SHORAD program, packaging our 300 kW laser for field testing against advanced threats, and we remain on track to scale to 1 megawatt under the Office of the Undersecretary of War for Research and Engineering (OUSW R&E) HELSI program.

2. Laser Sensing

We have a long track record of delivering highly reliable lasers and subsystems for precision guidance and threat detection. Our laser sensing portfolio supports missile guidance, proximity detection, ranging, and countermeasures, and is embedded in multiple long‑running defense programs. We believe these applications will continue to grow for years to come, supported by ongoing development of advanced lasers for mission‑critical systems.

3. Advanced Manufacturing

Our high‑power lasers, combined with proprietary beam‑shaping technology, enable partners to manufacture metal parts more efficiently and effectively through additive manufacturing processes. In 2025, we made a deliberate shift to focus exclusively on additive manufacturing and exit commoditized cutting and welding markets. Additive manufacturing is increasingly vital for space, defense, and industrial applications, and adoption of this critical capability is accelerating.

Looking Ahead |Launching new products and scaling operations

We enter 2026 with $162 million in funded backlog. Early in 2026, we strengthened the balance sheet with a follow-on offering that generated $200 million of gross proceeds to accelerate new product launches, expand U.S. manufacturing capacity, and strengthen our supply chain.

Our priorities are clear: launch new high-power lasers into funded production programs with U.S. customers and allies; scale U.S. manufacturing with the quality and delivery rigor our partners depend on; de-risk critical components and deepen our domestic supply chain with key partners; and expand nLIGHT lasers across directed energy, sensing, and advanced manufacturing.

Our objective is straightforward: to build a durable, profitable company focused on the critical technologies essential to our nation.

Our Mandate |Maintain urgency and remain vigilant

A quarter century after founding nLIGHT, it is deeply rewarding to reflect on our leadership in high-power laser technologies that both create shareholder value and serve national priorities. Our technology stack has never been stronger. We are addressing pressing challenges in a rapidly changing world. The moment has never demanded more of us.

We are optimistic about what lies ahead. We are also clear-eyed. The world that shaped the previous decades is gone. The world we now serve demands the same urgency that guided us at our founding yet with greater vigilance.

I am proud of our employees, grateful for your trust, and energized by the important work ahead.

Chairman & Chief Executive Officer

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