You lifted them out of the pot, or worse, out of the oven, and the skins are shriveled and puckered instead of tight and glossy. I made plenty of these when I was starting out, and they traced back to the same root: bagels wrinkle after boiling when the rise gets spent before the oven takes its turn. Three things do that. The first two have done it to me plenty; the third is the reason my pot-to-oven routine exists. Here they are in the order to check them.
Cause 1: they boiled too long
Twenty seconds per side. That's my whole boil, every batch, and blowing well past it is the most reliable wrinkle-maker I know.
The boil has one job: set a thin skin around a ring that still has rising left to do. Leave the bagel in the water and it starts doing that rising in the pot instead, so by the time it finally reaches dry oven heat, the spring is gone. The skin set around a bagel that was going to get bigger, the bagel never did, and the extra skin settles into wrinkles. Same rule as finishing lumber. Lay a finish on wood that's still moving and the film buckles as the wood shifts underneath.
You can spot this one in the pot. An overboiled bagel balloons in the water, then goes into the oven and just sits there. If your boil runs minutes instead of seconds and your bagels wrinkle, this is almost certainly your answer. Count the seconds; don't guess.
Cause 2: the dough overproofed
An overproofed ring gives itself away during the boil: it doesn't puff at all in the water, it just holds whatever shape it had on the board. The fermentation already spent the dough's gas and strength on the counter, so there's nothing left for the pot or the oven to expand.
My guard is the float test. I drop one shaped bagel into cool water, and the moment it floats, the whole batch goes into the fridge to slow the fermentation down. Cold dough holds its remaining rise instead of burning through it. If your kitchen runs warm and you proof by the clock instead of by the float, overproofing will find you sooner or later; it found me.
Cause 3: they sat around after the boil
A boiled bagel is on a timer. That just-set skin is sticky and soft only briefly, and the oven needs it in that state; a skin that dries on the counter sets early, before the oven spring has finished pushing. The bagel puffs less, and the skin it already set hangs loose and wrinkles.
My routine keeps the window short: out of the pot, straight onto the soaked boards, and into the oven. Toppings get one minute, no more. If I'm not ready and a batch sits drying while I catch up, those bagels puff less in the oven; that's the whole reason the routine exists. Have the landing spot ready before the first bagel hits the water. The full pot-to-oven sequence is on our Using Your Bagel Board page.
The rolling boil isn't guilty
Plenty of advice out there says wrinkles come from water boiled too hard, and that you should hold a gentle simmer instead. I can't back that up. Every batch I make goes into a full rolling boil. Dropping the bagels in knocks the water down for a moment and it comes right back, and I've never traced a single wrinkle to the boil being too hard. Time in the water does the damage, not the bubbles. The only mischief a hard boil causes in my pot is bagels flipping themselves over before I get to them.
Why bagels wrinkle after boiling
Every wrinkled bagel is the same failure at a different station. The dough only holds so much rise. Something got there first: the counter, the pot, or the drying air between the two. Guard the rise and the skin comes out tight: fridge the batch when the float test passes, hold the boil to twenty seconds per side, and give every bagel somewhere to land that's headed straight for the oven.
Where to go next
Why Are My Bagels Flat and Dense?: wrinkles' sibling failure, with its own ranked causes.
The Secret to Shiny, Blistered Bagel Crust: what the boil is actually for when it goes right.
Our bagel boards: the gear half of the Cause 3 fix.