The Academy graduate, 17, has shown significant progress within the Suffolk club and has been rewarded with the deal, which also includes a 12-month option.
Crowe, a Wales Under-19 international, told Town's official website: "Obviously I'm delighted to have been offered a pro deal.
"This is a great football club and I feel I am learning all the time and making progress.
"I am training every day with Scott (Loach) and Dean (Gerken) and that is helping my development and I've got a fantastic coach in Malcolm Webster as well.
"I've been around the first-team this season and if I can put pressure on the two keepers then great, but my main focus at the moment is to be as good as I can be and play as much as I can for the Under-21s."
- Sports & Recreation