Blocking a sweater

I’m making a top down sweater. I finished the body but it’s tighter than I thought it would be. It’s 100% cotton, which is why I sized it small. Can I block it the 3" or so it needs? Thanks for your help!

That may help. Cotton stretches when wet. I have a top down raglan in a cotton/acrylic blend that fit wonderfully, then when I washed it, the sleeves must have got caught on something that pulled them. They’re about 6 inches too long now. :wink: I’m going to throw it in the wash again with the sleeves inside and hope for the best.