It depends. Some Customers with disabilities are able to preboard at the very beginning of the boarding process prior to general boarding. Preboarding is available for Customers with disabilities who need a specific seat to accommodate a disability, need assistance boarding the aircraft, or need to stow an assistive device.
A Customer Service Agent at the ticket counter or the departure gate can help with this accommodation, and you'll be asked questions to determine if you qualify. You'll receive a new boarding pass marked with PRBD if you qualify, which lets the Operations Agent at boarding know that you can preboard. Remember that you can't occupy an exit seat if you preboard.
One travel companion may preboard with you. If you feel you need an exception to this, please discuss your needs with a Customer Service Agent at the gate when requesting preboarding.
If you're preboarding because you need a specific seat, speak with the Operations Agent after getting your new boarding pass but before preboarding starts.
Customers with disabilities who simply need a little extra time to board or otherwise do not qualify for preboarding may board between the "A" and "B" groups, before Family Boarding. A Customer Service Agent at the ticket counter or departure gate can give you a new boarding pass marked with XT, which lets the Operations Agent at boarding know that you can board before Family Boarding.