The Reds’ vice-captain suffered a calf injury in the closing stages of last month’s win over Manchester City and has subsequently missed the last three matches – all defeats – against Chelsea, Everton and West Brom.
Van Gaal said: “Carrick is not available and it was more heavy than we thought.
“We tried everything but now we have to think about next season. He shall not play anymore this season, it’s better now to focus for him on next season and being fit to start.”
United’s Dutch boss, buoyed by clinching the signing of PSV winger Memphis Depay on Thursday, has once again expressed his concern over an inbalance in midfield and says he will address the issue in the summer transfer window.
“When you see the stats, it’s clear that he’s very important but that’s also because we have only one right-sided holding midfielder,” Van Gaal said.
“That’s what I have said all season that our selection is not balanced, and I want to restore that in the next transfer period. His career is not ending at 34, but for a professional football player, it’s close-by. That’s why I have to handle again in that position.”
Van Gaal has confirmed that Luke Shaw is available again as United head to Crystal Palace on Saturday Night Football, live on Sky Sports 1HD, but weekend may come to soon for Jonny Evans.
He said: “Evans and Shaw can play football or the game. Evans doesn’t have the match rhythm because he was injured for six weeks and after that he was suspended for six weeks, and after that he was injured again.”
Watch Crystal Palace v Manchester United live on Saturday Night Football on Sky Sports 1 HD from 4.45pm.