How common is it for customers with connecting flights to be routed through immigration check?

Question

On most flights I've taken, when landing at an international airport, in a country that I won't be visiting and isn't my final destination, I can just debark the plane and stay in the international terminal and then board another plane. It's only if I leave the international part that I have to pass through immigration.

But on a recent flight, all passengers who debarked were sent through one route that only led to immigration. Some of the passengers became very aggravated, refusing to cooperate with the officials who wanted to look at the passports, take photographs & fingerprints, as they said they were just passing through to their other flight.

Is that a common practice in some countries to require everyone to be processed through customs, even if they have connecting flights to destinations outside that country? Did the passengers have any right to refuse it?

Answer 1

First, remember that customs is for goods. Checks of passport and visas is usually called passport control or immigration.

It is always the case that you have to go through passport control in the US, and I believe there are a few other countries which do it as well: there is no sterile airside airport transit at all, everyone has to go through passport control, reclaim luggage, go through customs, and drop luggage for the next flight, even if checked through.

It is also the case in some airports which do not have sterile airside transit (usually smaller airports, but that includes quite busy airports like Luton in London for example, and a number of other airports used mostly by LCCs). But in those cases, airlines will usually not sell you connecting flights through those airports (so they are self-transfers).

Of course if you have a self-transfer and checked luggage you will need to go through passport control as well to retrieve your luggage and then go to departures to check in.

If you have multiple connections within the same country (or group of countries like the Schengen Area), it’s also a requirement to go through passport control at the first airport in the country/area and then through exit passport control at the last one.

This also applies when your arrival or departure airport is in the same country/area as the connection airport (and the other end of the itinerary isn’t). For instance if you fly JFK-FRA-ZRH you will go through checks in FRA, not ZRH (at least in theory — you could be subject to additional checks in ZRH even though you arrive from another Schengen Area country).

Same thing if you have to switch airports. Sometimes also if you have to switch terminals (may depend on the exact combination of terminals in some places).

In some airports, some transit passengers may also be isolated (right at the gate) and have their passports taken away during international transits. There could also be checks to ensure that they have an airside transit visa right at the gate, in situations which require one.

There’s also the case of US pre-clearance: if you fly to the US through an airport which has pre-clearance you will go through (US) passport control at that point (but you will then arrive in the US as a domestic flight without any checks there).

Without the details of the itinerary (origin and destination countries, all connection airports, the airlines involved, and whether this was a real connection or a self-transfer) it is difficult to say whether this was perfectly normal or if something went wrong, but I suspect the former rather than the latter. And if so, then, no, there’s no reason to complain.

Answer 2

It is quite common and depends on multiple factors. We often travel from Canada to another country via the US and, during the return trip, it is almost always the case that we pass through customs and immigration. The one exception from memory was Bahamas to Canada via the US. The other way, we generally do the US control when leaving Canada at the Canadian airport.

Also, going from Canada to any country in Europe via any other European country forces this to happen since customs and immigration is done at the point of entry in the EU. Earlier this month, I transited via Amsterdam on the way to Oslo and had to do customs and immigration in the Netherlands. Similarly on the return trip.

Even in some countries that have international-to-international transfer facilities, it can happen that you still have to do immigration when changing terminals, if the airport does not have an internal connection between the two.

ADDENDUM

This answer starts saying that it depends on multiple factors which it does. It would be rather hard to list every possible connection and figure out exactly the probability distribution with all combination of routes, airports and terminals. So while it is possible to point out which sub-case of the generalization does not apply, the reality is that there are plenty of cases when this happens. Examples above are from recent travel but are not meant to be exhaustive.

Answer 3

Is that a common practice in some countries to require everyone to be processed through customs, even if they have connecting flights to destinations outside that country?

Yes. It is standard practice in the US and Canada and a few smaller countries. The only exception for the US are so called pre-clearance airports, where you pass through US immigration at the departure airport. But you still need to go through immigration.

Did the passengers have any right to refuse it?

No. The responsibility of having the correct paperwork rests on the passenger and IATA offers online tools to help you do this. https://www.iatatravelcentre.com/passport-visa-health-travel-document-requirements.htm

Some of the passengers became very aggravated,

That sounds unlikely. Most passengers should know that this would happen and they MUST have proper documentation to enter the transit country otherwise the airline would not have allowed them to board in the first place.

There are always exceptions: sometimes there is an emergency or some other issue that triggers extra controls and unforeseen entry into the country, but these are handled on a case by case basis. It would help if you could add the details of where exactly that happened and which flights were involved.

Answer 4

Yes, it's very common, especially when you aim for the cheapest flights. Always true if you go through the US or Canada. Sometimes if you're connecting to or from a discount airline you have to go through customs and immigration even if the airport has sterile transfer for other flights on the same airline or at the same terminal.

Certainly going through incoming and outgoing customs and immigration multiple times on one trip can be tiring and stressful with long queues and sometimes rude officials when your aim is just to GTFO.

Going on one ticket, avoiding countries without sterile transfer facilities, and either flying direct or connecting at a hub within your destination or origin country can avoid those hassles, but usually you pay a premium for it.

Sadly, those most interested in saving money (young and footloose, the self-employed etc.) are also those most likely to face hassles at the otherwise unnecessary inspections. But even those more "mature" can suffer from schlepping luggage and their carcasses through long queues, inspections, bag drops and back through the miserable security theatre yet again.

Regarding customs vs. immigration-- I'm hard-pressed to think of any time when they are not handled together- either both or none (including checked luggage). Sometimes (as in pre-clearance) it seems like they're not, but they are.