Global Positioning System III / GPS Block III is the Lockheed Martin-built U.S. military navigation-satellite block that modernized the GPS constellation with M-code, the L1C civil signal, higher accuracy, and stronger anti-jamming performance. The ten-space-vehicle series launched from 2018 through 2026, reached full operational acceptance in May 2026, and is treated here as a relationship-only precision position, navigation, and timing space system rather than a direct battlefield weapon.
GPS III Block III uses sequential space-vehicle designations for the ten-satellite production block, followed by the GPS III Follow-On / GPS IIIF line.
GPS III launch history includes Delta IV Medium+ (4,2) and Falcon 9 missions.
| Launcher | Launcher type | Launch evidence |
|---|---|---|
 | Medium-lift orbital launch vehicle | ULA says a Delta IV Medium+ (4,2) rocket delivered the second GPS III spacecraft, Magellan, from Space Launch Complex-37 to medium Earth orbit. Sources: Delta IV GPS III - United Launch Alliance (ULA) Rocket Launch |
 | Reusable two-stage orbital rocket | Space Systems Command records Falcon 9 launches for later GPS III missions including SV09 in January 2026 and SV10 in April 2026, the final GPS III satellite. Sources: GPS III SV09 launch - Space Systems Command, U.S. Space Force delivers final GPS III to orbit |
GPS III is best read here as a space-enabled military support system. Official sources describe a ten-vehicle Block III production run that strengthens position, navigation, and timing services for military and civil users, but the sources reviewed for this entry do not identify a GPS III space vehicle as a direct weapon used in a named armed conflict.
SV01 through SV10 make up the GPS III block, with GPS III Follow-On / GPS IIIF identified as the next generation.
GPS III is the first GPS satellite generation described by SSC as broadcasting M-code, the encrypted military GPS signal for more secure and jam-resistant service.
SV10 completed the block in April 2026, and GPS public status material records operational acceptance on May 12, 2026.
The Air Force and mission partners launched the first GPS III satellite from Cape Canaveral on SpaceX's Falcon 9, opening the GPS III era.
Sources: First GPS III satellite successfully launched
GPS.gov's space-segment chronology records the first GPS III satellite as healthy and active to users in January 2020 after on-orbit checkout.
Sources: Space Segment | GPS.gov
GPS.gov records the fifth GPS III satellite as healthy and usable, showing the family moving deeper into operational service.
Sources: Space Segment | GPS.gov
Space Systems Command and Combat Forces Command launched the Lockheed Martin-built GPS III SV09 on a Falcon 9 from Cape Canaveral, adding another M-code satellite to the constellation.
Sources: GPS III SV09 launch - Space Systems Command
Space Systems Command delivered GPS III-8, Space Vehicle 10, to orbit on Falcon 9, completing the ten-satellite GPS III block and adding demonstrations for crosslinks, timing, laser ranging, and antenna technology.
Sources: U.S. Space Force delivers final GPS III to orbit
The 2026 GPS Public Interface Control Working Group presentation records SV10 operational acceptance on May 12, 2026 and lists ten GPS III satellites declared operational.
Sources: 2026 GPS Public ICWG Presentation
