SHORT ANSWER
The best way to prepare a pet for the risks of an international move is to start early, before you have a firm move date, and work through four areas in order: a fitness-to-fly exam with a USDA-accredited veterinarian, weeks of kennel acclimation at home, a travel date chosen with temperature and routing in mind, and paperwork checked against your destination country's current rules. Most risks in pet relocation, from stress and heat exposure to rejected documents, are lower when owners give themselves months of lead time instead of weeks. U.S. federal guidance also advises against sedating pets for flights without a veterinarian's approval and a test dose beforehand.
When families think about risk, they usually picture the flight. In practice, the risks spread across the entire process. A pet can experience stress from an unfamiliar kennel, noise, and handling. Older pets, pets with existing health conditions, and snub-nosed breeds face added physical strain. Extreme heat or cold can limit when a pet is allowed to fly. And on the administrative side, a missed test, an expired certificate, or a mismatched microchip number can stop a pet from boarding or entering the destination country.
The good news is that nearly every one of these risks can be reduced with preparation. The sections below walk through what to do, in roughly the order you should do it.
The single most protective step is starting early. According to USDA APHIS, you should contact a USDA-accredited veterinarian as soon as you decide to travel internationally with a pet. That vet will help you determine your destination country's entry requirements, including vaccinations, tests, and treatments, and guide you through getting a USDA-endorsed health certificate.
Some destinations require blood tests followed by mandatory waiting periods that add months to the process. If you discover those requirements late, the risk is not a stressful week. It is a delayed move, or a pet who has to stay behind while the rest of the family relocates.
During a recent Pet Travel Insider live Q&A, I put it simply: "I think timeline and kennel acclimation are both huge ones. I don't think it's ever too soon to start. I've never heard of someone planning too far in advance for an international pet move."
For a deeper look at how destination rules, USDA paperwork, and airline policy have to line up, see our Rules & Risks of Pet Travel complete guide.
Before you focus on paperwork, ask your veterinarian a direct question: is my pet healthy enough to fly? Age, weight, heart and respiratory health, anxiety level, and breed all play a role. This exam is separate from the official health certificate appointment that happens close to departure, and it gives you time to address issues while there is still room in the schedule.
Breed deserves special attention. Brachycephalic, or snub-nosed, dogs and cats such as Pugs, French Bulldogs, and Persian cats have shorter airways, and many airlines restrict or decline them on certain routes. The Department of Transportation notes that each airline sets its own animal policies, so check the specific carrier's rules for your route before you plan around it. If you have a flat-faced pet, our guide to relocating overseas with flat-faced dogs and cats covers the extra steps involved.
Kennel acclimation is the part of preparation owners have the most control over, and it makes a real difference. The U.S. Department of Transportation advises pet owners to accustom their pet to the kennel it will be shipped in before traveling and to confirm that the door latches securely.
A practical approach looks like this:
The goal is a pet who treats the kennel as a safe, familiar space, not a strange box that appears on the worst day of the move.
Many owners assume sedation will make a flight easier. Federal guidance points the other way. The Department of Transportation advises owners not to administer sedation without a veterinarian's approval, and to give a test dose before the trip to see how the pet reacts. The International Air Transport Association (IATA) states that it does not encourage the use of sedatives and tranquilizers for animals traveling in the cabin or cargo hold because of the potential for adverse effects.
If your pet is anxious, talk with your vet well before departure about options, and lean on kennel training as your primary stress-reduction tool.
Heat and cold are real risks for animals in transit, and U.S. rules reflect that. Under the USDA's Animal Welfare regulations, the ambient temperature in airport animal holding areas containing dogs or cats must not fall below 45°F or rise above 85°F for more than four consecutive hours while animals are present (9 CFR 3.19). Carriers also may not accept a dog or cat unless their holding areas meet the minimum temperature requirements, or unless the owner provides a veterinarian's certificate, dated no more than 10 days before the pet is handed to the carrier, stating that the animal is acclimated to lower temperatures.
In practice, this means your travel season can shape your timeline. Airlines may decline or reroute pets during periods of extreme heat or cold, so build flexibility into your plan if you are moving in summer or winter. The Department of Transportation also suggests choosing nonstop flights when possible and avoiding connections and heavy holiday or weekend travel.
Documentation problems are one of the most common reasons a pet move goes sideways. USDA APHIS warns that destination countries set their own pet entry requirements and that those requirements can change at any time, so you must verify them every time you plan to travel. Do not rely on what worked for a friend's move last year.
To reduce paperwork risk:
The Department of Transportation offers several travel-day steps worth following. Avoid giving your pet solid food in the six hours before the flight, though a moderate amount of water and a walk before and after the flight are advised. Write your name, address, and phone number on the kennel, make sure your pet wears an ID tag with the same information, and consider a temporary tag with your destination address. Bring a current photo of your pet in case they are lost.
Risk planning should cover the return trip too. The CDC's dog import requirements depend on where your dog was vaccinated and which countries it has been in during the six months before entering the U.S. A dog that has been in a high-risk country for dog rabies and is not vaccinated will not be allowed to enter. Keeping your dog's U.S. rabies vaccination records organized now can make a future return much simpler.
Pet owners who have been through cargo moves consistently point to crate training as the step they would not skip. In an r/dogs thread titled "My dog and I moving overseas HELP!!!," one commenter advised: "You need to start slowly adjusting him to being in the crate. If he isn't trained to handle the crate in the apartment, he likely will be" far more stressed on the flight itself (r/dogs discussion). It is the same advice federal guidance gives, coming from people who have lived it.