A surgical instrument includes a first jaw defining a channel, a second jaw including an anvil plate, a staple cartridge, and a drive beam. The staple cartridge is received in the channel and includes a sled, a knife blade, a plurality of staple pushers, and a plurality of staples. The sled is movable into engagement with the staple pushers to eject the staples from the staple cartridge. The knife blade is secured to the sled and is movable between raised and lowered positions.