Anderson was waived last month by Houston. He was in his sixth season with the Texans, where he played under current Redskins offensive coordinator Kyle Shanahan.
Balmer was a first-round draft pick by San Francisco in 2008. He was cut by Carolina on Sept. 1.
Johnson had been on Minnesota's practice squad.
Stallworth had only five catches, while neither Byrd nor Scott played for the Redskins this season. Thompson has been up and down between the practice squad and main roster.
Also, running back Tristan Davis was cut from the practice squad.