The modification is a sole-source, cost-plus-incentive fixed-fee vehicle with a work completion date of Sept. 30, 2016.
Under the contract, Raytheon will procure materials for building 29 SM-3 Block 1B missiles, which are kinetic weapons.
The missiles, without explosive warheads, destroy their target through impact equivalent to a 10-ton truck traveling at 600 mph.
Raytheon said it has delivered more than 150 earlier model SM-3s to the U.S. and Japanese navies and is on schedule to begin deploying the upgraded Block 1B missile by 2015.
The Block 1B will be deployed ashore as well as aboard ships.
The missile is for defense against short- to intermediate-range ballistic missiles. They weigh 1.5 tons and are 21.6 feet long. They have an operational range of 270 nautical miles.
Additional details of the contract modification were not given.