flying Phoenix to JFK to Rome on honeymoon...Where do we clear customs?
 

We booked a trip flying from Phoenix to New York JFK to Rome. All flights are operated by Delta and our bags will be checked to Rome. We have a tight connection time at JFK and are wondering if we have to go through customs at JFK or just when we arrive in Rome? Please help!

There is no Customs leaving the US (Customs is re declaring any goods being imported)

Now if you actually mean Immigration (passport control) - again, except for looking at your passport, when you check in there is no Immigration when leaving the US

So both are only at Rome.

there is no immigration control leaving any country. Just isn't possible.

>there is no immigration control leaving any country. Just isn't possible.

Not in the OP's case but yes, a number of countries do have immigration/passport control upon exit.

It's a semantics point... Immigration is entrance INTO a country, by definition.

You clear both immigration and customs your first stop outside your home country, so in this case... Rome.

Yes, but semantics aside, it is immigration officials who perform the exit functions including stamping passports as necessary. Point is there can be queues for the process regardless of IM or EM functionality.

But not at all relevant to the OP's question so why muddy the waters?

When leaving the US, the airline is responsible for checking your passport to see that it is in order. If they carry a passenger who does not have the correct documentation, they can be fined by the destination country and will have to return the passenger. As you are checking your baggage through to Rome, Delta may want to see your passport at Phoenix, particularly if they are issuing the boarding passes through from JFK to Rome. You may also have to show your passport at the departure gate at JFK.

You will have to go through Italian (EU) immigration on arrival in Rome.

Immigration and customs in Rome on the way TO Italy. Both in JFK on the way back. That's where you have to worry about the tight connection. But you may still have to change terminals at JFK, and that can take time because it's a long walk (though all within security), but most Delta flights are now in Terminal 4.