Originally Posted by
blondietink
Yes, they have to check your passports at the ticket counter before you can check in. This applies to all international flights as far as I know. Had to do this for Costa Rica, Cancun, Bahamas, etc.
I had no problem checking in online to fly from PHL to Punta Cana, and vice versa.
If you don't have your passport info with Southwest in your reservation, maybe that's where the problem was. But, the need to check your passports before you can check in is false. You are permitted to check in online.