Layovers and customs questions

Just checking to note the difference between customs (goods), passport control (immigration) and security. I'll take a stab at the Toronto part of it. We flew via Toronto to Amsterdam a couple of years ago. Arriving in Toronto, we had to go through a special Canadian "transit" passport check, since we were not staying in Canada. We still needed time to get from one gate area to another. We did not have checked bags, but there would be no reason for going through customs since anything you've checked won't be entering Canada either.

For the return, Toronto has a US passport control & customs station you go through to get on your US-bound flight, so that you dont have to go through it when you land in the US. You may have a Canadian transiting passenger passport check there as well.

I can only answer part of this. On the way back to the US, if you go via Dublin or Toronto you will go through both customs and immigration in those cities, since they both have US Customs and Immigration offices there; so when you land in the US it will be like coming from a domestic flight. But if you go via London, you'll have to go through customs and immigration in the first US city you land in.
Going over, I don't think you'll have to go through either customs or immigration in any of those cities unless it's your final destination. Otherwise, you'll just be in transit and customs and immigration will depend where your next and last stops are.

Best if you give your starting airport in the US and ultimate destination.

Are these true connecting flights on one ticket, and will you have luggage checked through to your final destination or hand luggage only?

What happens at transit airports depends where you're going to/coming from.

Adding to what Stan said: the U.S. is the only place we’ve been that requires the retrieval of baggage and a customs check for travelers in transit from other countries. Some have security checks, but no customs if your bags are checked through to your final destination. It is something to keep in mind when estimating whether you have enough time between flights.
As to the question being “ dumb” or “played out,” better safe than sorry. It IS confusing, especially when you add to the mix that you go through U.S. border control in Toronto (at least that’s how I remember it).

Thanks to everybody so far.

ramblin' on, my options are all single ticket, will have a minimum of 2 pieces of checked-in luggage.

The Dublin route would be booked entirely with British Airways, but the DCA-DUB flight would be Aer Lingus, and the DUB-FCO would be BA. All others are single airline.

DCA-YYZ-FCO
DCA-LHR-FCO
DCA-DUB-FCO
DCA-EWR-FCO
DCA-ATL-FCO

FCO-YYZ-DCA
FCO-LHR-DCA
FCO-EWR-DCA
FCO-ATL-DCA

edit: Also, yes, I conflated or combined customs and passport control. I tend to think of them as one big, painful process :)

Thanks for clarifying.

For Dublin and London, you stay airside. You won’t cross the Irish or UK borders. On one ticket you won’t collect luggage (providing you stay at one London airport and not have to cross from LHR to LGW, for example) as it will be checked through to Florence.

You will go through immigration when you enter Italy and customs when you collect your luggage.

For your flights returning to the US and connecting in Newark or Atlanta, the procedure is as follows:

You get off the plane and go through US immigration. You then proceed to baggage claim, and pick up all your bags. You then go through customs. If you have checked luggage, you deposit it at the recheck desk, just outside the customs area door. You then go to the gate for your next flight, passing through security on the way (since you've been outside security when you exit the customs area).

At least in the past, you could save a LOT of time in line by having either Global Entry ($100 for five years, requires application process) or by using the Mobile Passport app (free if you enter your data each time, $15 per year if you want it to store your data between trips).

I'd allow 3 hours at any US airport for this process. You never know how many planes are arriving at the same time as yours, or how many agents are on duty.

For your flights departing the US and connecting at Newark or Atlanta, there is no customs or immigration on departing the US.

In Atlanta, you can get from one gate to another without having to go through security. In Newark, it depends on which airlines are involved. All of terminal C (United) is in one security area, but terminal B (used by Delta and most non-US airlines like British Airways and Virgin Atlantic) is in several sub-areas. At least in the past, the Delta flights were clustered in one security area, so you didn't have to go through security again, but of course this can change. If you're going between terminals (A, B, C) you always have to go through security.

Thanks, everybody!

All of you have been very helpful. And much more on point that the handful of various and mixed/contradictory discussions and articles I've read elsewhere.

For connecting at Heathrow and Toronto, their websites have very good connection tools. Put in all your details (including flight numbers), and you'll get detailed directions and estimated times (key word, of course, is estimated).

Heathrow: https://www.heathrow.com/connecting-flights

Toronto: https://www.torontopearson.com/en/connections

For Dublin, here's their page on the procedure for connecting to a US bound flight, complete with video: https://www.dublinairport.com/flight-information/travelling-to-usa/usa-preclearance

Harold, those are awesome. Thanks!

The connection link on Heathrow.com works so well, easy.

I have connected in U.S., Canada, and Europe. I actually think it is easier to connect in Europe where all you have to do is get from one gate to another and then deal with customs after return to your U.S. destination. I connected in London last year coming from Edinburgh as it was a Sunday and a U.S. connection point was not available. I had previously avoided connecting in Europe, thinking it would be more difficult but found it less stressful than doing it in the U.S. or Canada. I really hate having having to retrieve luggage and recheck it in a U.S. connection point.

Of course, I will put up with a certain amount of extra stress if the price is right!

BethFL, the last time I came back with a change at Heathrow, it was the same thing. EDI-LHR-IAD, and I remember just walking from gate to gate, no problems. But that was a long time ago so I wanted to make sure before I finalize any tickets.

Now you have me thinking about Edinburgh! I had a lot of fun in that town.

I have connected in U.S., Canada, and Europe. I actually think it is
easier to connect in Europe where all you have to do is get from one
gate to another and then deal with customs after return to your U.S.
destination.

There is a reason one of the "rules" in international air travel is "if you're not flying to/from the US, never fly via a US airport".

However, for the easiest possible connection avoid connecting in the UK where you will have to reclear security unless you're arriving on a domestic flight.

There are a lot of red flags coming up.

First, I doubt many of your flights are from DCA (Reagan National). Did you mean IAD (Washington Dulles)?

Next when you say one ticket who is doing the ticketing? An Airline or a third party like Expedia? Aer Lingus and British Airways are not in the same alliance?

Some of your routing does not make sense. British Airways does not fly nonstop between Dublin and Rome. Could it be an Brtish Airways codeshare using Aer Lingus equipment? It will say who is operating the flight . Don't just look at the flight number.

Upon your first entry in the U.S., you will go through U.S. immigration and customs. However, if returning from Ireland or Canada--for your purposes--you go through U.S. immigration and customs there so when you arrive in the U.S. you just go about your business. In London, you follow "Flight Connections" and there is no need to go through British immigration and customs unless it really isn't one ticket and then you will have to retrieve your luggage.

Don't assume that because you are buying this all together than it is really one ticket.

Upon your departure, if you are really on one ticket, your luggage should be checked through to Rome.

When you connected at Heathrow from Edinburgh of course if was easy. It was a domestic fight.

Frank: Nope. No red flags, and no aggregator sites like kayak or cheapoair or whatever are in play. All looked up directly on the airlines' own sites. And, yes, all of those I listed are from and to DCA, except for BA/Aer Lingus, which is out of IAD, and the DUB-FCO route is actually Aer Lingus now that I look at it. FWIW, the BA site is most definitely displaying Aer Lingus flights in its search results and I can book the US-Rome legs on Aer Lingus and the Rome-US legs both through BA and in the same transaction with BA... so mea culpa. But the underlying questions remained the same.

Badger: Thanks for that word of advice. That is helpful,

BA and Aer Lingus have the same parent company and I forget they do codeshare European flights.

DCA-YYZ-FCO
DCA(IAD)-LHR-FCO
DCA(IAD)-DUB-FCO
DCA-EWR-FCO
DCA-ATL-FCO

If on one ticket, your luggage will be checked through to Rome. No exit immigration in the U.S. No immigration in Canada. No immigration in London or Dublin. You will go through Schengen immigration in Rome.

FCO-YYZ-DCA--you will go through U.S. customs and immigration in Toronto. No Canadian immigration. Nothing in the U.S.

FCO-LHR-DCA(IAD)--No immigration in London but you will have to go through security again. You will go through U.S. customs and Immigration in the U.S.

FCO-EWR-DCA--you will go through U.S. customs and immigration in Newark.

FCO-ATL-DCA--You will go through customs and immigration in Atlanta.

Remember, you go through Schengen exit immigration in Rome.

Just verifying that you are on a US passport if flying via Canada. The US has an agreement, but some other nationalities need a transit visa.

Frank: That's awesome. Thanks!

Bets: Yes, US passports. Thanks!

However, if returning from Ireland or Canada--for your purposes--you go through U.S. immigration and customs there so when you arrive in the U.S. you just go about your business.

Yes, as I stated, and as Frank II confirmed, if you fly back to the US from Toronto or Dublin, you go through US customs and immigration there, and when you arrive in the US it's the same as arriving on a domestic flight. You deplane, get your luggage, and you're off.

Preclearance explanation. Common at Canadian airports with departures for the USA plus airports like Dublin. Preclearance allows travelers departing or transferring at preclearance airports to fly to US airports without border and customs controls or bypass those that do.

https://en.wikipedia.org/wiki/United_States_border_preclearance

The United States federal government operates border preclearance
facilities at a number of ports and airports in foreign territory.
They are staffed and operated by U.S. Customs and Border Protection
(CBP) officers. Travelers pass through U.S. Immigration and Customs,
Public Health, and Agriculture inspections before boarding their
aircraft, ship, or train. This process is intended to streamline
border procedures, reduce congestion at U.S. ports of entry, and
facilitate travel between the preclearance location and U.S. airports
unequipped to handle international travelers.

https://www.cbp.gov/border-security/ports-entry/operations/preclearance

Customs and Border Protection (CBP) Preclearance is the strategic
stationing of CBP personnel at designated foreign airports to inspect
travelers prior to boarding U.S.-bound flights. With Preclearance,
travelers then bypass CBP and Transportation Security Administration
(TSA) inspections upon U.S. arrival and proceed directly to their
connecting flight or destination

I looked up the airport codes, and from Washington D.C. there are a lot of other options that in my opinion sound much better than the ones you have mentioned. If you don't want to book Alitalia I would suggest TAP via Lisbon or Austrian via Vienna.

Badger: Yes, I am considering the direct flight with Alitalia. It offers reduced complications - though Alitalia's financial situation gives me pause. Still, I may take a bet on them.

I can understand your hesitation to book with Alitalia, although they seem to have more lifes than a cat. But transfering at a smaller airport, like Vienna or Lisbon will usually make the transfer much smoother.

But transfering at a smaller airport, like Vienna or Lisbon will
usually make the transfer much smoother.

Badger, that's a great point that I hadn't considered. Thank you.

And, yes, Alitalia certainly seems to have nine lives, if not more!