Fit-to-Fly Certificate for Pregnancy in Phuket: How Many Weeks and What Airlines Ask For

Clinically reviewed by Dr. Ponlawat Pitsuwan, Physician, Takecare Clinic Phuket. Last reviewed: September 2026

You flew into Phuket at 26 weeks for a babymoon in Kata, everything went smoothly, and now you are 30 weeks and trying to book the flight home. The airline’s check-in page shows a pregnancy policy you did not read on the way out. You need a letter from a doctor, it has to say specific things, and your flight is in two days. This situation walks through our door regularly.

Getting a fit-to-fly certificate in Phuket is straightforward if you know what you need and where to go. The complication is that airline rules are not uniform. Week limits differ by carrier, certificate requirements differ, and the validity windows mean a letter you get today may not cover your return leg. This guide covers all of it, specific to the airlines flying through HKT.

What Airlines Actually Need and Why the Rules Differ

Airlines set their own pregnancy policies, and they do not all agree. Most use 28 weeks as the point where they require a physician-signed letter for a singleton pregnancy. Before 28 weeks, most carriers will let you board without documentation, though you should always verify with your specific airline before you travel.

The variation is largely about liability, not medicine. Each carrier sets its own risk threshold and its own expiry rules for the certificate. What is consistent is the principle: the closer you are to your due date, the more documentation the airline wants.

For twins or a multiple pregnancy, every major carrier brings the cut-off forward. Most require a letter from 28 weeks, and many will not carry a passenger with a multiple pregnancy beyond 32 weeks. If you are carrying twins, check your airline’s policy before you book, not the day before you fly.

Airline-by-Airline Week Limits at a Glance

This is where most guides fall short. They cite 28 weeks and 36 weeks as if those are universal. They are not. Several carriers flying in and out of HKT have rules that will catch you off guard.

Two things stand out for Phuket travellers. First, AirAsia cuts off at 35 weeks, not 36. Many passengers assume 36 weeks is the standard and plan accordingly. If you are on an AirAsia flight home and you are 35 weeks plus a day, you will not board. Second, Cathay Pacific requires documentation from 19 weeks, which surprises almost every patient who comes in having assumed they were well below the threshold.

Always confirm your airline’s current policy directly before your trip. Policies change, and this table reflects guidelines at the time of writing.

What Your Certificate Must Actually Say

This is the gap that causes real problems at check-in. A letter that says "this patient is pregnant and feels well" is not a fit-to-fly certificate. Airlines are specific about what they need, and a vague letter will be rejected.

A valid certificate must include your full name, current gestational age at the date of travel, estimated due date, confirmation that the pregnancy is singleton or multiple, and a statement that there are no complications. It also needs the physician’s full name and licence number, the date of issue, and the explicit phrase "Fit to Fly." Most airlines require official clinic letterhead.

Bring your passport and any antenatal scan reports or pregnancy records to your consultation. The scan report matters because it confirms your estimated due date, which is the figure the physician signs against. At Takecare Clinic Phuket, the certificates we issue are formatted to meet these requirements as standard, in English, signed by a licensed physician, and ready within the same visit.

Certificate Validity Windows and the Return-Flight Trap

Here is the situation I see regularly. A patient flew into Phuket at 28 weeks. She is now 31 weeks and flying home in three days. She got a certificate before she flew out. That certificate is almost certainly expired. Thai Airways requires a letter dated within 7 days of departure. Singapore Airlines allows 10 days from the first flight in the itinerary. If your outbound and return flights are more than a week apart, you will very likely need a fresh certificate in Phuket before you board the return leg.

This is not a policy trick. It is because your clinical situation changes as your pregnancy progresses. The certificate is a snapshot of your condition at a specific gestational age, not a blanket clearance for the whole trip.

If you flew into Phuket without a certificate because you were under the threshold, and you are now past it for the flight home, you need one issued here. A same-day walk-in appointment at our clinic on Prachanukhro Road in Patong is the practical answer for most patients in this position. You can find full details on our medical certificate service page.

When a Walk-In Clinic Cannot Issue the Letter

Most patients in a straightforward pregnancy will walk in, be seen, and walk out with their letter. But there are situations where I would not issue a fit-to-fly certificate, and patients need to understand why.

A physician cannot safely sign the letter if there are signs of pre-eclampsia, such as high blood pressure combined with headache or visual changes. Severe or sudden swelling, any vaginal bleeding, signs of ruptured membranes, known placenta praevia, or an uncertain due date with no scan to confirm gestational age would also prevent issuance. In these cases, the right place is a hospital with obstetric facilities, not a walk-in clinic.

If you have any of these concerns, message Takecare Clinic on WhatsApp before you come in. We can tell you quickly whether a walk-in visit is appropriate or whether you need a higher level of care.

Other Things Worth Raising at the Same Visit

If you are coming in for a fit-to-fly certificate, use the same visit to ask a few other questions. There are Phuket-specific risks for pregnant travellers that are worth a brief conversation.

Zika virus has been documented in Thailand, including Phuket. It is not a widespread outbreak risk right now, but mosquito protection matters. DEET-based repellents are considered safe in pregnancy at standard concentrations, and you can find them at any pharmacy on the island. On long-haul flights home, DVT risk is higher in pregnancy. Compression socks and regular movement through the cabin are both sensible steps.

One more thing: most standard travel insurance policies exclude pregnancy-related claims from a certain week. Check your policy before you need it. If you are in the third trimester and your policy has a pregnancy exclusion, you are covering obstetric care out of pocket in Phuket if something goes wrong. Extended pregnancy travel cover exists and is worth arranging before you leave home.