The Air Force birthday is September 18. The U.S. Air Force became a separate military service on September 18, 1947, when the National Security Act of 1947 took effect and W. Stuart Symington was sworn in as the first Secretary of the Air Force. Before 1947, American military aviation was part of the Army. On September 18, 2026, the Air Force turned 79.
Why is the Air Force birthday on September 18?
The Air Force birthday is on September 18 because that is when the National Security Act of 1947 put the new service into operation. President Harry S. Truman signed the act on July 26, 1947, but the Air Force did not exist as a separate department until September 18, when its first Secretary took office. The act split the U.S. Army Air Forces, which had existed since June 1941, out of the Army. General Carl A. Spaatz became the first Chief of Staff of the Air Force on September 26, 1947, as noted by the 433rd Airlift Wing.
| Birthday | September 18, 1947 |
|---|---|
| Created by | National Security Act of 1947 (signed July 26, 1947) |
| Predecessor | U.S. Army Air Forces (1941 to 1947) |
| Department | Department of the Air Force (shared with the Space Force) |
| Active-duty airmen | 311,920 (DOD active-duty demographics, September 2025, via Air & Space Forces Magazine) |
| 2026 anniversary | 79th |
How does the Air Force celebrate its birthday?
The Air Force celebrates its birthday with Air Force Balls, cake-cutting ceremonies and messages from the Secretary and Chief of Staff of the Air Force. Many bases hold their ball on a weekend close to September 18, so dates vary. The Air Force shares its department with the U.S. Space Force, which grew out of Air Force Space Command and has its own birthday on December 20.
Are Air Force veterans who served before 1947 Air Force veterans?
Airmen who served before September 18, 1947, served in the Army Air Corps or the Army Air Forces, which were part of the Army. Many World War II aviators and ground crew still identify with the Air Force, which carries on their units and traditions. If you are buying for a World War II or Korean War era veteran, ask how they describe their own service.
How can you honor an Air Force veteran on September 18?
You can honor an Air Force veteran on September 18 with a message, a call or a gift they can wear or display. Our Air Force veteran gifts include the Air Force Veteran Hoodie and the Air Force Memorial Flag Case, which holds a folded flag. Read how to display a burial flag before you choose a case. Muster USA orders ship within 1 to 3 business days and arrive in 5 to 12 business days, so order at least 3 weeks before the date. Delivery times are on our shipping policy page.
