The 21-year-old joins from Hull City on an emergency loan until the end of the season.
A graduate of Manchester United's Academy, Stewart spent time on loan with Yeovil Town and Hull City before securing a permanent deal with the Tigers in January 2011.
The following season the winger would go on to play 32 times for the Hull, but a change of management saw opportunities limited this term as the player joined fellow Championship side Burnley on loan where he made nine appearances.
Subject to Football league clearance, Stewart has been signed in time for inclusion in the squad for Saturday's match against Peterborough United. He will wear squad number 32.