YSS · York Space Systems Inc.

52% Year-on-Year Growth Driven By Strong Execution as a Mission Prime York Space Systems Inc. (NYSE: YSS) (York) today announced financial results for the fourth quarter and full year ended December 31, 2025. For the year ended December 31, ($ in thousands, except percentages) 2025 2024 % Change Revenue $ 386,203 $ 253,531 52 % Gross profit 75,460 32,421 133 % Net loss (84,537 ) (98,911 ) (15 %) Adjusted EBITDA (non-GAAP) $ (8,271 ) $ (42,966 ) (81 %) * See definition and reconciliation of Adjusted EBITDA to net loss under “Non-GAAP Financial Measures” and “Reconciliation of GAAP to Non-GAAP Measures.” “2025 was the year York defined what a modern mission prime looks like,” said CEO Dirk Wallinger. “We emerged as a leading provider to the Department of Defense’s Proliferated Warfighter Space Architecture, measured by spacecraft on orbit, number of contracts, and mission types. We delivered the first Tranche 1 Transport

York Space Systems (York) (NYSE: YSS), a leading, US-based national defense and commercial prime providing a comprehensive suite of mission-critical solutions, today announced it has acquired Orbion Space Technology (Orbion), a Michigan-based manufacturer of flight-proven electric propulsion systems. The acquisition strengthens York’s integrated space ecosystem and directly supports the strategy the company outlined at the time of its initial public offering: aligning its technology roadmap, investing in domestic production capacity, and delivering systems that work reliably and at scale. Final testing of an Orbion Aurora integrated propulsion system prior to delivery. Founded in 2016, Orbion designs and manufactures Hall-effect electric thrusters for constellation-scale satellite missions. Its Aurora propulsion systems are produced domestically and are already flying on York-built spacecraft supporting U.S. national security missions, including satellites operating as part of fielded

York Space Systems Inc. (NYSE: YSS) will release its financial results for the quarter and full year ended December 31, 2025 after the close of market on Thursday, March 19, 2026. In conjunction with this release, York will host a conference call to review its financial results for the quarter and the year, discuss its outlook for the future and may disclose other material developments affecting its business and/or financial performance. Listeners may access the conference call live via an audio webcast. Thursday, March 19, 2026 3:00 pm Mountain Time (5:00 pm Eastern Time) Webcast: https://events.q4inc.com/attendee/615953366 York’s financial results release will be available after the close of market on March 19, 2026 on York’s website at http://ir.yorkspacesystems.com . An audio webcast replay of the conference call will be available for one year at http://ir.yorkspacesystems.com . About York Space Systems York Space Systems (NYSE: YSS) is a leading, U.S.-based national defense and

York Space Systems (York), a modern defense prime built for speed and scale, announced the pricing of its upsized initial public offering of 18,500,000 shares of its common stock at a public offering price of $34 per share. In addition, York has granted the underwriters a 30-day option to purchase up to an additional 2,775,000 shares of its common stock at the initial public offering price, less underwriting discounts and commissions. The shares are expected to begin trading on the New York Stock Exchange on January 29, 2026 under the ticker symbol “YSS,” and the offering is expected to close on January 30, 2026, subject to customary closing conditions. Goldman Sachs & Co. LLC, Jefferies, and Wells Fargo Securities are acting as lead bookrunning managers for the proposed offering. J.P. Morgan and Citigroup are acting as joint bookrunning managers. Truist Securities, Baird, and Raymond James are acting as bookrunners. Canaccord Genuity, Needham & Company, and Academy Securities

York Space Systems (York), a modern defense prime built for speed and scale, announced it has launched the roadshow for its proposed initial public offering of 16,000,000 shares of its common stock. In addition, York intends to grant the underwriters a 30-day option to purchase up to an additional 2,400,000 shares of its common stock at the initial public offering price, less underwriting discounts and commissions. The initial public offering price is expected to be between $30 and $34 per share. York has applied to list its common stock on the New York Stock Exchange under the ticker symbol “YSS.” Goldman Sachs & Co. LLC, Jefferies, and Wells Fargo Securities are acting as lead bookrunning managers for the proposed offering. J.P. Morgan and Citigroup are acting as joint bookrunning managers. Truist Securities, Baird, and Raymond James are acting as bookrunners. Canaccord Genuity, Needham & Company, and Academy Securities will serve as co-managers. The proposed offering