The M249 SAW is manufactured in the United States by the subsidiary FN Manufacturing LLC, a company in Columbia, South Carolina (FN America), and is widely used in the U.S. Armed Forces. The weapon was introduced in 1984 to address a lack of sustained automatic fire capability at the squad level. The M249 SAW combines the rate of fire of a machine gun with the accuracy and portability of an assault rifle.

The M249 SAW is gas operated and air-cooled. It features a quick-change barrel (enabling the operator to rapidly replace an overheated or obstructed barrel) and a folding bipod attached to the front of the weapon (an M192 LGM tripod is also available.) The M249 SAW is normally belt-fed, although it is technically compatible with STANAG magazines (such as those used in the M16 and M4).

The M249 SAW has seen action in major conflicts involving the United States since the U.S. invasion of Panama in 1989. In 2009, the United States Marine Corps selected the M27 Infantry Automatic Rifle to partially replace the M249 in USMC service.[7]