Crossing a land border with a dog takes paperwork in both directions, and the part that catches people out is usually getting back into the United States. Since August 2024, every dog entering the US needs a CDC Dog Import Form receipt, a microchip and proof that it's at least six months old. That applies to your own American dog coming home from a weekend in Vancouver or Tijuana. A puppy under six months can leave the US legally and then be refused on the way back.
Mexico has added a second hurdle. Because of New World screwworm, a dog driving into Mexico has needed a USDA-accredited vet's inspection certificate since August 3, 2026, and a dog returning needs a separate screwworm freedom certificate. Both are dated within five days of the crossing. Canada is much simpler, but you still have to carry a rabies certificate and declare your dog.
This guide is for owners driving across and coming back: road trips, RV travelers, snowbirds and families with a cabin over the border. If you're moving for good, see our guides to pet transport to Canada and pet transport to Mexico. Rules can change quickly, so check the agency pages linked here in the week you travel.
What you need at each crossing
| Crossing | Dog needs | Timing | Common trap |
|---|---|---|---|
| US to Canada | Rabies certificate from a licensed vet (under 3 months exempt, with proof of age) | Vaccination within 3 years of entry | Forgetting to declare; no originals |
| Canada to US | CDC Dog Import Form receipt, microchip, at least 6 months old, looks healthy | Receipt lasts 6 months | Puppy under 6 months can't re-enter |
| US to Mexico | NWS inspection certificate signed by a USDA-accredited vet; inspection at the border office | No more than 5 days before entry | Ticks hold the dog; food taken away |
| Mexico to US | CDC receipt, microchip, 6 months old, screwworm freedom certificate | Inspected within 5 days before crossing | Finding an authorized vet in time |
Driving into Canada
Canada asks for proof of rabies vaccination and not much else for a personal pet dog traveling with its owner. USDA APHIS says a dog older than eight months needs a certificate from a licensed vet showing vaccination within three years of entry. A dog younger than eight months traveling with its owner also needs current rabies proof, except that dogs under three months are exempt from vaccination and need proof of age. There is no quarantine, and no APHIS endorsement for the ordinary owner-accompanied pet. Certain assistance dogs have exceptions.
Canada's border agency adds three points that matter at the booth. You must declare your animal, because officers can refuse, confiscate or detain undeclared animals, including family pets. You must be the importer, with proof of ownership, and the dog must stay with you and not be handed to someone on arrival. And you should travel with the original paper copies of your documents, not just a photo on your phone.
A dog you are bringing for breeding, resale, adoption, fostering, rescue, shows or research counts as a commercial import, which is a completely different process. Don't try to bring a rescue dog over as a pet on a day trip.
Cats need a rabies certificate from a licensed vet too, showing vaccination within three years of entry, and kittens under three months are exempt. No health certificate is required for a cat, according to APHIS.
Coming back from Canada
Canada is on the CDC's low-risk track, which is the easiest path into the US. The CDC requires that your dog be at least six months old, carry a microchip that a universal scanner can detect, look healthy on arrival and have a Dog Import Form receipt. The form is free and online, and there is one per dog. You can fill it out on the day of travel or up to six months ahead. The CDC says dogs can enter at any airport, seaport or land border crossing.
If you cross often, there is good news. The receipt is valid for six months and can cover several entries, as long as your dog hasn't been in a high-risk country in the past six months. If you are traveling from a different low-risk country, you need a new form listing that country as the departure point. Print the receipt or keep it on your phone, but Canada wants paper, so keep everything together in one folder.
The biggest trap is the six month rule. It applies to US-born puppies as well, and a Canadian visit that lasted only an afternoon doesn't change it. Canada doesn't require a microchip, so you could get in without one and then be stuck on the way home. If your dog isn't chipped, get it done before you leave. See our guide to bringing a dog from Canada to the US for more.
Driving into Mexico
This has become the harder direction. According to APHIS, Mexico requires an NWS Inspection Certificate for Pet Dogs, effective August 3, 2026. A USDA-accredited veterinarian signs it no more than five days before your dog enters Mexico. APHIS endorsement isn't required. Without it, your dog can be denied entry or held at the border.
The inspection doesn't end there. You go to the Agricultural and Livestock Health Inspection Office (OISA) with your dog in a clean carrier. A SENASICA official checks that your dog shows no signs of infectious or contagious disease, is free of external parasites and has no fresh or healing wounds. If parasites are found, your own vet must treat them. If ticks are found, your dog is held until SENASICA confirms they aren't exotic to Mexico or under a control program, and you pay any costs.
Check your carrier before you leave. A dirty carrier, disposable bedding, toys or food can be disinfected or removed and destroyed, and only the food needed for the day of arrival is allowed. Don't pack a week's kibble in the crate. A thorough flea and tick treatment and a bath before you go can save you hours. Enforcement at land crossings has been reported as uneven, but the rule applies whether or not anyone stops you.
Cats don't need the certificate, and a cat shouldn't be added to the dog form, because that invalidates it. SENASICA still inspects cats at the OISA with the same checks.
Coming back from Mexico
Mexico isn't on the CDC's high-risk list for rabies, so the same CDC requirements apply: six months old, microchip, form, healthy appearance. What makes this direction harder is the USDA. APHIS says dogs coming from Mexico need a screwworm freedom certificate, and the dog must be inspected for screwworm within five days before shipment. A clinical vet trained and authorized to sign for the official government veterinarian can issue it, and authorized vets are listed in the MVRA Directory. There is no required template.
That five-day window controls your whole trip. For a short visit, you may be able to use a nearby authorized vet just before you head home. For a longer stay, book the appointment and work backward from your crossing date. KGNS reported in June 2026 that Customs and Border Protection says it will strictly enforce the rules, that returning US pets are covered, and that unprepared travelers may be delayed or turned back. Our guide to bringing a dog from Mexico to the US goes through it step by step.
Your dog's travel history can change everything
The easy track only applies if your dog hasn't been in a high-risk country in the previous six months. If you are driving a long route through Central or South America, or your dog arrived from a high-risk country recently, the rules get much tougher. You may need vet-completed rabies forms and entry through specific airports, and a land crossing may not be possible. Check the CDC high-risk country list first, and see our guide to importing a dog into the US.
A simple checklist for the glovebox
Keep one folder in the car with everything in it: the rabies certificate, microchip number, CDC receipt, any screwworm or NWS certificate, your vet's contact details and a recent photo of your dog. A week before you leave, confirm the microchip scans, and check that the rabies vaccine won't expire during your trip. Check the agency pages again, since these rules have changed several times in the past year alone.
At the booth, tell the officer that you have a dog before they ask. Keep your dog secured and calm, ideally in a harness or crate, because an officer may want a look. Be ready for a stop at secondary inspection, and don't plan a tight schedule on the far side. Allow for heat, too. A long summer line at San Ysidro or Peace Arch is a real risk in a car with a dog, so keep the air conditioning on and bring water. Our guide to road trips with a dog has more on keeping your dog comfortable.
Service dogs and rental cars
Service dogs still have to meet entry rules for each country, though Canada exempts certified personal-category assistance dogs from rabies vaccination. Don't assume a US service dog is excused from the CDC requirements. If you are taking a rental car or ferry across the border, check its pet rules and its cross-border rules separately. Our guide to the Washington State Ferries and the Coho covers the sea route to Victoria.
Timing it: a weekend in Canada and a week in Mexico
For a weekend in Vancouver or Montreal, the work is mostly done at home, and you can start any time. Dig out the rabies certificate, check the date and scan the microchip. Fill out the CDC form at home and save the receipt. Then put the originals in the folder. If everything is in order, this takes about half an hour, and the same receipt can cover your next trip within six months.
A week in Baja or Sonora takes more planning. Book your US vet for no more than five days before you cross, and make sure that vet is USDA-accredited, since not every clinic is. Treat your dog for ticks and fleas before the appointment. Pack a clean carrier and one day's food, and buy the rest in Mexico. While you are there, find an authorized vet in the MVRA Directory and book the return inspection for no more than five days before you head home. If you decide to stay longer, you'll need to move that appointment.
Cats, multiple dogs and snowbirds
The CDC Dog Import Form is for dogs, so a cat doesn't need one to re-enter from Canada or Mexico. A cat should still look healthy on arrival, and it makes sense to carry a current rabies certificate, since states and officers may ask for it. Traveling with several dogs means one CDC form per dog, and one certificate per dog for Mexico.
Snowbirds face the tightest timing, since a winter in Mexico needs the certificate twice each season, and the rules could change between your trips south and north. Build in a few spare days around your return, and keep the contact details of a vet near your crossing point in case of a delay. Our guide to snowbird pet transport has more on seasonal moves. If you'd rather not drive, a transporter who handles cross-border trips can sometimes manage the logistics, but you remain responsible for checking the paperwork is right.
US state rules still apply
Once you are back in the US, you are subject to state rules as well as federal ones. Most states require a current rabies vaccination, and some have their own import rules for pets from outside the state, including screwworm-related orders that have appeared in 2026. If you are not returning to the state you left from, check the rules at your destination. Hawaii and Alaska are the strictest, and our moving to another state with a dog guide is a good starting point.
If something goes wrong at the border
Stay polite and ask exactly what is missing, because officers have limited discretion and often can't waive a federal rule. If you are missing a CDC receipt, you may be able to complete the form on your phone on the spot, though don't count on a signal or on the officer's patience. A missing screwworm certificate is harder, and you may need to go back and see a vet. Expect delays if your dog has fresh wounds or parasites. Keep your phone charged, know where the nearest vet is on both sides of the crossing, and allow plenty of spare time on your first trip.