Houston needed to jump to the top of the allocation order to sign United States national team member DaMarcus Beasley, who is expected to finalize negotiations with the Texas side later this week.
Creavalle, 23, joins Toronto after making 72 appearances for the Dynamo in all competitions. He should be available for selection by TFC in Saturday's regular season match against Sporting Kansas City at BMO Field.
“Warren is a player that we have been watching closely for some time now and we feel his versatility will be a welcomed addition to our club,” TFC general manager Tim Bezbatchenko said in a statement. “Houston expressed interest in switching allocation positions so combined with our interest in Warren this move was a win-win for both clubs.”