Traveling with Pets

The short version

Taking a cat to Mexico is still simple. Taking a dog got more complicated in 2026. New World screwworm, a parasitic fly that had spread north through Mexico, was detected in Texas in June 2026, and both countries now want proof that dogs crossing the border are free of it. A dog's round trip now involves two time-sensitive certificates, one from a US vet before you go and one from an authorized Mexican vet before you come back, on top of the CDC rules that took effect in 2024.

Here is the sequence for a dog, start to finish:

1. Make sure your dog is at least 6 months old and has a microchip that a universal scanner can read. Puppies under 6 months cannot enter the US at all, so they cannot make the round trip.
2. Check your airline's pet rules and reserve your pet's spot when you book; cabin spaces are limited per flight.
3. Within 5 days before you arrive in Mexico, visit a USDA-accredited veterinarian for the New World screwworm inspection certificate.
4. At the airport or border in Mexico, present your dog to SENASICA, the agriculture inspection service, for a quick check.
5. Before your trip home, fill out the free CDC Dog Import Form online.
6. Within 5 days before you return to the US, have an authorized Mexican veterinarian inspect your dog and issue a screwworm-freedom certificate.
7. At the US border or airport, show the CDC receipt and the screwworm certificate; officers may inspect your dog.

Entering Mexico: the SENASICA rules

Mexico's agriculture and food safety agency, SENASICA, inspects pets at airports and land crossings through its inspection offices (OISA). As of the USDA's September 21, 2026 update, the rules for dogs and cats coming from the US are as follows.

What happens at the airport

After immigration and baggage claim, take your pet in its carrier to the SENASICA counter before you leave the customs area. The officer checks your paperwork for a dog, looks your pet over, and checks the carrier. If everything is in order, you receive an import certificate (Certificado Zoosanitario de Importación), normally free of charge. Keep it with your travel documents.

If the officer finds fleas, ticks or other external parasites, you must have a veterinarian of your choice treat the animal, at your expense, before it is released. If ticks are found, the animal can be held at the inspection office until SENASICA confirms they are not a species foreign to Mexico or under a control program. That can mean hours, or longer if a lab test is needed.

Practical tips for a smooth inspection

• Give a flea and tick preventive at the right interval before travel, and comb your pet the day before you fly.
• Line the carrier with something you do not mind losing, or nothing at all. A dirty carrier, or one with disposable bedding, toys or food, is disinfected and its contents thrown away.
• Pack only one day's food, in a sealed bag. Buy the rest in Mexico; major brands of dog and cat food are sold in supermarkets and pet stores across the country.
• Bring your pet's rabies certificate and vaccination record anyway. Mexico does not list them as entry requirements for dogs and cats from the US, but airlines, hotels, groomers and boarding kennels in Mexico often ask, and they help prove ownership.
• Do not add a cat to a dog's paperwork. APHIS warns that listing a cat on a dog or bird inspection form invalidates the form and can get the animal refused or held.

If you go back and forth often, SENASICA has a frequent traveler pet program; the APHIS Mexico page lists how to contact it. Birds, ferrets and other animals have different and much stricter rules, and some exports to Mexico were halted during the 2026 outbreak.

The 2026 screwworm rules, explained

New World screwworm is a fly whose larvae feed on the living flesh of warm-blooded animals, entering through wounds, the navel of newborns or the nose and ears. It had been moving north through Central America and Mexico for several years, and the USDA has treated Mexico as affected since November 22, 2024. In early June 2026, the USDA confirmed the first cases in the US, in cattle in South Texas, followed by cases in other animals, including a dog.

Timeline

• Around June 8, 2026: the USDA briefly halted exports of pet dogs and several other animals to Mexico.
• June 10, 2026: pet dogs were taken off the halted list and could travel to Mexico again under the existing procedures.
• August 3, 2026: Mexico began requiring a screwworm inspection certificate for every pet dog arriving from the US.
• September 21, 2026: APHIS reminded travelers that mistakes on the certificate can lead to dogs being denied entry or held up at Mexican ports.

Going south: the US certificate

Any USDA-accredited veterinarian can issue the screwworm inspection certificate; many general-practice vets in the US are accredited, but ask when you book. The exam must take place no more than 5 days before your dog enters Mexico, and the certificate does not need an APHIS stamp. APHIS has posted instructions for vets on its pet travel site, so ask yours to follow them exactly. American Airlines and Delta both check the certificate at check-in, and American applies it to service dogs too.

Coming north: the Mexican certificate

APHIS requires every dog entering or re-entering the US from Mexico, including US dogs coming home from vacation, to have a screwworm-freedom certificate. The dog must be inspected within 5 days before it travels to the US, and the certificate must state either that it is free of screwworm or that it was infested, treated and quarantined until free. For dogs coming from Mexico, the certificate can be signed by a Mexican veterinarian trained and authorized to sign on behalf of the official government veterinarian, known in Mexico as an MVRA. APHIS has no required template, and the dog is inspected at the US port of entry along with its papers.

• Find an authorized vet early. Not every Mexican vet can sign. SENASICA publishes a directory of authorized vets, but it is incomplete in some towns and lists few vets outside big cities, so call clinics as soon as you arrive and book the appointment for a weekday.
• Mind the 5-day window. If a flight delay or a change of plans pushes your crossing past 5 days, you need a new certificate.
• Carry the original. Keep the signed paper in your carry-on with your passport and CDC receipt.
• Cost. Clinics set their own fees. One report from Puerto Vallarta in 2026 put the visit at roughly MX$700 to MX$1,400 (about $38 to $76).

Check your dog every day while you travel, especially around the ears, nose, genitals, navel and any scratch or wound. Draining or slow-healing wounds, maggots, a bad smell or unusual discomfort need a vet the same day. Do not try to remove larvae yourself.

Flying with a pet

Small dogs and cats that fit under the seat in front of you can usually fly in the cabin. Larger pets have far fewer options, and summer heat rules out many trips.

In the cabin

• American Airlines charges $150 per kennel each way to Mexico. Soft-sided carriers up to 18 × 11 × 11 inches (46 × 28 × 28 cm) work on all flights; hard-sided carriers have smaller limits on regional jets. Pets must stay in the closed carrier under the seat.
• Delta charges $200 each way on international flights, including Mexico. It recommends a soft-sided carrier no larger than 18 × 11 × 11 inches, requires ventilation on four sides for international trips, and allows no pets in some premium cabins. Delta also requires cats entering the US to be at least 16 weeks old.
• Other US airlines differ widely. Some do not fly pets in the hold at all, and policies and fees change often, so check your airline's pet page and call to add your pet when you book.
• Mexican airlines (Aeroméxico, Volaris and Viva Aerobus) accept small pets in the cabin on many routes, with weight limits that include the carrier and per-flight caps. Aeroméxico also carries larger pets, with restrictions for snub-nosed breeds and in hot months. Rules differ by route, so check each airline's site.

In the hold or as cargo

American accepts checked pets only for active-duty US military and State Department Foreign Service staff on orders; everyone else with a large pet must use its cargo service. American will not fly pets in the hold if the current or forecast temperature anywhere on the itinerary is above 85°F (29.4°C), and between May 1 and September 30 it will not carry them in the hold to, from or through Phoenix, Tucson, Las Vegas or Palm Springs. It does not accept snub-nosed breeds such as bulldogs, pugs, boxers, Persians or Himalayans as checked pets.

Service and emotional support animals

US airlines carry trained service dogs in the cabin free of charge, but they no longer treat emotional support animals as service animals, so those fly as regular pets. Service dogs are not exempt from Mexico's screwworm certificate or from the CDC and APHIS rules for coming back.

Driving across the border with pets

Driving is often the easiest way to bring a large dog, and many people do it for weekends in Baja or Rocky Point. You still need the paperwork.

• Going south. Dogs need the screwworm certificate from a US-accredited vet, dated within 5 days. Enforcement at land crossings varies: you may be waved through, but random and targeted checks happen, and if you are sent to the SENASICA module without valid papers your pet can be held, turned back or tested at your expense.
• Food. The one-day rule applies by land too. Leave the big bag at home and buy food in Mexico.
• Insurance. Your US auto policy does not cover you in Mexico; you need Mexican liability insurance. See driving and border crossings.
• Heat. Northbound waits at busy crossings like San Ysidro can stretch for hours in the sun. Bring water and a bowl, run the air conditioning, and never leave a pet in a parked car.
• Coming north. Have the CDC Dog Import Form receipt and the Mexican screwworm-freedom certificate ready for CBP. Finish or throw away pet food bought in Mexico before the line, since meat-based products may be taken.
• State rules. If you are driving through Texas, check whether the state's screwworm orders affect your route; they mainly target livestock. Your home state may have its own rules for pets returning from Mexico.

Coming back into the US

CDC rules for dogs

Since August 1, 2024, the CDC has applied one set of rules to all dogs entering the US, including pets returning from vacation. Mexico is not on the CDC's list of high-risk countries for dog rabies (last updated April 15, 2026), so a dog that has been only in Mexico and the US in the past 6 months needs to:

• Be at least 6 months old on arrival
• Have a microchip readable by a universal scanner (an ISO-standard 15-digit chip is the safe choice)
• Appear healthy on arrival
• Have a receipt from the CDC Dog Import Form, one per dog

The CDC Dog Import Form is free and online. You can submit it on the day of travel, but CDC suggests doing it anywhere from a few days to 6 months ahead. The emailed receipt can be printed or shown on your phone, is valid for 6 months, and can be reused for several entries as long as your dog does not visit a high-risk country and the departure country on the receipt matches. Under these rules your dog can come back through any airport, seaport or land crossing, and the CDC does not ask for a rabies certificate for dogs from low-risk countries.

On top of the CDC rules, you need the APHIS screwworm-freedom certificate described above.

Cats

The CDC dog rules do not cover cats, and the APHIS screwworm certificate applies to dogs. Cats must appear healthy, and CBP may look them over. Some US states require a current rabies vaccination for cats, and Delta requires cats entering the US to be at least 16 weeks old, so carry your cat's vaccination record.

Bringing home a Mexican dog

Falling for a street dog is common. The same rules apply: the dog must be at least 6 months old, microchipped, healthy, registered on the CDC form and certified screwworm-free by an authorized Mexican vet within 5 days of travel. Puppies under 6 months must wait in Mexico until they are old enough. Local rescue groups often know vets who handle this paperwork every week.

Pet-friendly travel in Mexico

Mexican cities, especially Mexico City, are dog-loving places. In Condesa and Roma you will see dog walkers with a dozen leashes, dogs on restaurant terraces, and the off-leash areas in Parque México and Parque España busy every evening. Elsewhere it varies.

• Hotels. Many boutique hotels and some chain hotels accept small dogs, usually with a fee and a weight limit. Most big all-inclusive resorts do not accept pets. Vacation rentals are often the easiest choice; get the pet permission in writing.
• Restaurants and cafés. Outdoor tables are often fine, especially in Mexico City, Guadalajara, San Miguel and beach towns. Ask before you bring a dog inside.
• Beaches. Rules vary by town. Many public beaches, especially those with Blue Flag certification, ban dogs, and some towns tolerate leashed dogs early and late in the day. Ask locally and look for signs.
• Getting around. In some cities the Uber app offers a pet-friendly ride option. Long-distance bus companies generally do not take pets other than service animals; ask before you book. Ferries have their own rules, so ask at the ticket office. Rental cars may charge cleaning fees.
• Heat and pavement. Walk early and late. Midday sand and pavement can burn paws, and snub-nosed breeds struggle in the humid lowlands.
• Manners. Keep your dog leashed, carry bags, and be aware that many people in Mexico are wary of big dogs.

Moving to Mexico with pets for a long stay? The same entry rules apply, and long stays covers renting with animals.

Vets and health risks

Mexico has well-trained veterinarians (look for the title MVZ, médico veterinario zootecnista), private clinics in every city, and 24-hour animal hospitals in the big cities. In areas with many Americans, such as San Miguel, Lake Chapala, Puerto Vallarta, Los Cabos and the Riviera Maya, you will find English-speaking vets. A routine visit usually costs far less than in the US. Pet stores and vet clinics sell the common flea, tick and heartworm preventives.

Health risks to know

• Ticks and tick-borne disease. Brown dog ticks are common, and ehrlichiosis, a tick-borne infection, is widespread in Mexican dogs. Keep your pet on a tick preventive and check daily.
• Heartworm. Present in warm, humid areas. Ask your US vet about prevention before you go.
• Leptospirosis. Spread through water contaminated by animal urine, more common in the rainy season. Keep dogs out of puddles and standing water.
• Parvovirus and distemper. Circulate where many dogs are unvaccinated. Keep vaccines current and keep your dog away from street dogs.
• Toads and scorpions. Large toads in the tropical lowlands secrete a toxin that can kill a dog that mouths one. Drooling, pawing at the mouth or seizures are an emergency: rinse the mouth with water and get to a vet.
• Heat stroke. The most common preventable emergency. Shade, water and no midday exercise.
• Screwworm. Treat any wound promptly and check it daily.

Street dogs

You will see free-roaming dogs in much of Mexico. Many are community dogs that belong to a neighborhood, sleep in the same doorway and are fed by locals. Most are calm and avoid people.

• Do not approach a dog that is eating, guarding puppies or part of a group, especially at night on rural roads and beaches.
• Keep your own dog away from street dogs, to avoid fights and disease.
• If a dog threatens you, stand still, avoid eye contact, and back away slowly. Pretending to pick up a stone usually sends it off.
• Do not feed dogs at restaurant tables; it encourages them to hang around diners, and owners will thank you.

If you are bitten or scratched

Wash the wound right away with soap and running water for 15 minutes, then see a doctor the same day. Mexico was the first country the World Health Organization validated, in 2019, as having eliminated rabies passed from dogs to people. Rabies still circulates in bats and wild animals, though, so any bite from an animal of unknown status deserves a medical assessment and possibly rabies shots. Public health centers and private hospitals in Mexico can give post-exposure treatment. See health.

Helping

Many towns have volunteer rescue groups and low-cost spay and neuter campaigns, often run with help from foreign residents. Donations, supplies from home and volunteer time all help. Some groups recruit travelers as "flight volunteers" to escort adopted dogs to the US; with the 2026 screwworm and CDC rules, ask exactly which papers are ready before you agree.

Pet travel checklist

• Dog at least 6 months old, with a working, universally readable microchip
• Airline pet reservation and the right size carrier
• Dogs: screwworm inspection certificate from a USDA-accredited vet, dated within 5 days of entering Mexico
• Rabies certificate and vaccination record (not required by Mexico, but often asked for)
• Flea and tick treatment before departure; a clean, empty carrier
• One day's food only
• Pet-friendly lodging confirmed in writing
• Name and number of an authorized Mexican vet (MVRA) near your departure point
• Dogs: screwworm-freedom certificate from that vet, dated within 5 days of returning
• CDC Dog Import Form receipt, on paper and on your phone
• Water, bowl and shade for border lines or layovers
• Your pet's records, and the contact for a 24-hour vet at your destination

Planning a trip around a pet? Our trip planning service can find pet-friendly lodging and line up vets on both sides. For everything else about preparing, see plan a trip.