The aircraft include the C-17 Globemaster III, the F/A-18E/F Super Hornet, the F/A-18 EA/18G Growler and the F-15E Eagle.
The follow-on contracts from Boeing Defense Space and Security to GKN's U.S. subsidiary are worth $850 million.
GKN Aerospace has been the sole-source supplier for items such as internal structures, external surfaces and wing leading and trailing edges for these aircraft since the company acquired the Boeing Fabrication Operations facility in St. Louis a decade ago.
"These latest contracts are a clear indication of the consistent performance of our St. Louis facility and the strength of our working relationship with Boeing," said Kevin Cummings, GKN president and chief executive officer of Aerostructures, North America.
GKN PLC is a global engineering business serving the automotive, aerospace and land systems markets. It has operations in more than 30 countries.