WASHINGTON — When Amazon gets to town, it’ll have one of the area’s biggest government technology contractors as a neighbor.

McLean, Virginia-based Booz Allen Hamilton, with more than 12,000 employees spread across two dozen offices in the Washington region, has signed a lease to expand its space in Crystal City.

Booz Allen has 25,000 employees at 80 locations worldwide.

Its space at JBG Smith’s 1550 Crystal Drive in “National Landing” will total 84,000 square feet when its new lease commences in September — about 10,000 square feet more than it currently has at the location.

Booz Allen will relocate from the building’s 11th floor to the 3rd floor.

JBG Smith is giving the 109,000-square-foot 1550 Crystal Drive a top-to-bottom makeover and will be anchored by a 49,000-square-foot Alamo Draft House and a yet-unnamed grocery store.

Additions will include new restaurants, retail and bars.