Layovers and connecting flights with a dog

In short

• A dog changing planes in the US is exempt from CDC rules only if all four conditions are met: cargo or checked baggage, no customs clearance, stays with the airline, final destination outside the US.
• A dog in the cabin never qualifies for the exemption.
• Changing airlines often means clearing customs, and clearing customs means entering the country.
• A layover in a high-risk country counts as a visit if your dog clears customs there.
• Foreign-vaccinated dogs from high-risk countries must land directly at their animal care facility’s airport, with no US connection before clearance.

The four conditions for a US layover exemption

A dog that only passes through a US airport on its way to another country does not need to meet CDC entry requirements, but only if every one of these is true:

1. It travels as cargo or as excess (checked) baggage.
2. It does not go through US customs.
3. It stays with the airline during the layover, until its next flight.
4. Its final destination is another country, not the United States.

If even one condition fails, your dog is treated as entering the US. It then needs a CDC Dog Import Form receipt and every document that matches its pathway. A dog that is refused entry is sent back to its last departure country, at your cost.

Cabin or cargo: why it matters

The exemption is written for dogs in the hold. A small dog flying in the cabin with you cannot use it, whatever the rest of the itinerary. The CDC also notes that a dog in the cabin may have to clear customs with its owner, and clearing customs counts as entering the country.

In practice: if your dog flies in the cabin and your trip touches US soil, plan as if your dog enters the US.

Changing airlines during a connection

When your dog moves from one airline to another, it no longer “stays with the airline” for the whole layover, so condition 3 fails. Changing airlines can also require clearing customs, which means entering the country.

Book your dog on a single ticket with one airline (or check exactly how your airlines transfer animals) if you want to rely on the exemption. Each airline has its own pet policy too, see airlines and pets.

Connecting through a high-risk country

The CDC looks at where your dog has been in the last 6 months. A layover can add a country to that list.

• If your dog clears customs in a high-risk country during a layover, the CDC considers that it entered that country. On arrival in the US, it must meet the high-risk requirements, even if its trip started in a low-risk country.
• If your dog stays airside with the airline and never clears customs, the layover does not count as a visit.

Example: your dog flies from Paris to Miami with a connection in Bogotá. If it changes planes without clearing Colombian customs, it stays a low-risk dog. If it clears customs in Bogotá (for example to change airlines or for an overnight stop), it becomes a dog that has been in a high-risk country, and needs much more paperwork.

If you are not sure what will happen during the connection, ask your airline before you book. See the high-risk country list to check your connecting airports.

Connecting inside the US after you arrive

Once your dog has entered the US with the right documents, a domestic connection is usually simple. The important exception is the foreign-vaccinated dog from a high-risk country.

These dogs need a reservation at a CDC-registered animal care facility (a private facility where your dog is examined and vaccinated on arrival). The CDC requires that:

• the dog arrives by air at the airport where its facility is located;
• there is no layover at another US airport before that;
• the dog is cleared at the facility before continuing its trip, which may take more than one day.

So a dog from Brazil with a facility reservation in Miami must fly into Miami directly. It can only take a domestic flight to Chicago after release from the facility. Facilities exist at a short list of airports, and there is none in Alaska, Hawaii or the US territories, so these dogs cannot enter there.

Before you book a trip with connections

1. Write down every airport where your dog changes planes.
2. Check whether any of those countries is high-risk.
3. Ask each airline whether your dog will clear customs during the connection.
4. If your dog flies in the cabin or changes airlines, assume it enters the country.
5. For foreign-vaccinated dogs, book a direct flight into the facility’s airport, see animal care facilities.