In Pressero you can enter an address in Puerto Rico TWO ways:
1) with US as the country and Puerto Rico as the province/state
2) with Puerto Rico as the country
The pricing for shipping may vary by the carrier depending upon how the user has the address formatted. it will also vary between our old shipping integrations and our new V2 shipping integrations. For example, the new UPS V2 integration will only return a price if you set up the address in Pressero with address configuration #2 (Puerto Rico as the country). The old UPS integration will accept address configuration #1 (US as the country). We highly recommend switching to our new V2 shipping integrations. You can set this up in Preferences > Shipping.