Your serial number is stamped under the bottom bracket, the part of the frame where the right and left pedals connect in the middle. Flip your bike over and look closely; a flashlight helps, since the numbers are stamped directly into the metal, not printed on a sticker.
Full walkthrough with photos: How to find your bike's serial number
Record your serial number and register your warranty. We don't automatically capture serial numbers, so registering ensures we have yours on file. While you're at it, register with Bike Index too. It deters theft and improves recovery odds if your bike is ever stolen.
