A friend of mine recently flew to the United States via Air Canada.

He says he cleared customs in Canada and the plane arrived at a domestic terminal.

Why is that?


2 Answers 2


What your friend experienced is something called Preclearance. This is a program where you pass through US immigration and customs at your departure airport, and arrive into the US as (basically) a domestic passenger.

Preclearance originally started as a way to allow flights from select Canadian airports to land in US airports that don't have immigration/customs facilities - as the passengers passed through US immigration/customs before departure the flight could land at any US airport, regardless of facilities.

It has since expanded to cover most flights from Canada, as well as some flights from select other international locations (all of which are listed on the page linked above).

  • 3
    Notable airports that don't have US immigration/customs facilities (and so would be unavailable to flights without preclearance) are New York-Laguardia and Washington-Reagan. I believe that Chicago-Midway was like this as well until the mid '00s, but that could just be a false memory. Aug 18 at 15:36
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    Preclearance, in addition to allowing flights to airports with no customs/immigration also allows passengers to arrive as if they are coming from a US airport. Flights from Canada generally don't arrive at the international arrivals terminal, and making itineraries with connecting flights through US airports is much easier because of Preclearance. As a note, preclearance from Canadian airports is not new; I can remember my father explaining it to me in the mid 1960s
    – Flydog57
    Aug 18 at 18:15
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    @Flydog57 So you're saying that they "arrive into the US as (basically) a domestic passenger" ?
    – Doc
    Aug 18 at 19:09
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    @Doc: Yes, if I fly from Montreal (YUL) to El Paso through DFW on American, I am very likely to arrive in DFW at one of terminals A or C (both domestic arrivals terminals). I get off the plane like any other domestic arrival passenger. Any checked luggage will be tagged all the way through to El Paso. I just have to walk a few gates over (or take the secure-side train) to the El Paso gate. It makes for a seamless transfer
    – Flydog57
    Aug 18 at 20:02
  • @Doc precleared flights arrive as domestic flights. The point of the program is to avoid the passengers and goods having to go through immigration and customs clearance on arrival. At international airports, the passengers and goods are treated as if they were arriving from within the US. (I recall reading somewhere that CBP reserves the right to re-clear a precleared aircraft when it arrives in the US, but I've never heard of that actually happening, so I suppose it's very infrequent.)
    – phoog
    Aug 20 at 10:32

because of the Canada–U.S. Agreement on Air Transport Preclearance you can clear customs at select airports at departure

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    To be certain, "you can clear" doesn't mean that the passenger gets to choose, only that it's possible for it to happen. (In fact it's nearly certain that it will happen.) Every flight from Canada to the US is either entirely cleared before takeoff or entirely cleared after landing. Passengers just do what they're told to get on the plane.
    – phoog
    Aug 17 at 15:59

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