What Happens If Your Arrival Card Does Not Match Your Passport
A typo in the TDAC is not a fine. But a wrong passport number at immigration is a fifteen-minute conversation with someone who can end your trip.
The Thailand Digital Arrival Card is free, official, and filed within 72 hours of arrival. It is also the document most likely to be filled in badly, because people do it on a phone in a hotel room at 11pm and because the form asks for your passport number twice in slightly different ways.
Last verified 30 September 2026.
First, what the card is not
The TDAC is not a visa. It does not replace one and it does not affect your permission to enter, which is governed entirely by your nationality and your visa status. Plenty of people enter Thailand having never filed one. You may be asked for it at immigration, and the fine for not filing is nominally 500 baht, and in practice the enforcement is inconsistent and almost never materialises at all.
That said, file it. It is free, it takes five minutes, and the reason to file it is not the fine, it is that the immigration officer is looking at your screen and having the form there makes the conversation short.
The three numbers that must be exact
Your passport number. This is the one that matters. A mismatch here is what turns a ten-second glance into a fifteen-minute conversation.
Your nationality. Select the one your passport says, not the one you feel most strongly. If you hold two passports and are travelling on the second, the card must say the second.
Your date of birth. The format on the form is day, month, year. Thai forms and the immigration system use that order. Getting it wrong is not a crisis but it is avoidable.
The address fields are much less critical. A hotel you have not booked yet, a hostel, a friend, the airport — all of these are fine. Nobody at immigration has ever asked me for proof of a Thai address, because the card is a health declaration, not a visa application.
What happens with each kind of mistake
A wrong passport number: usually fine, occasionally a conversation. If the name and nationality match, most officers correct it and move on. If the name does not match, or you have changed your name and the passport is old, it is harder.
A wrong date of birth: almost always fine. This is a health form, not a border control document, and nobody cross-references it against anything at the desk.
Filing it for the wrong entry: a real problem. One card per entry. If you fly out to Phuket and come back to Bangkok, you need a new one. Arriving with a card from your previous entry is the mistake that occasionally causes friction, because the QR code does not match the current arrival.
Filing it too early: minor. It is a declaration for the next 72 hours. Filing it a week out is technically wrong and practically nobody cares, because the officer is checking that the arrival date is close to today.
Filling in a fake hotel address: nobody checks, and I would still use a real one, because the form is a legal document and lying on a legal document is a bad habit to build a travel habit around.
What actually happens at the desk
The normal sequence at Suvarnabhumi immigration is: passport open, visa or exemption confirmed, arrival card located on your phone, arrival and departure stamps, done. That is two minutes.
The sequence when something is wrong is: passport open, question, question, officer decides whether it is a clerical error or a problem, stamp, done. Fifteen minutes is a common duration. Occasionally it becomes a referral to a supervisor, which is longer and involves explaining yourself twice.
None of this is about proving anything. The officer is trying to establish that you are the person in the passport and that your stay is legal. A TDAC mismatch does not threaten either of those things, so it is very unlikely to become serious. The exceptions are if your name in the card belongs to someone else, which is a copy-paste error, or if the passport number is someone else's, which means you used the wrong form.
How to not have this problem
Fill the card in the airport, not the night before. You are there, you have the passport in your hand, and it removes the entire category of error.
Screenshot the QR code. Battery dies, airport wifi fails, and a screenshot works every time. This is the single most useful thing anybody does for this process.
Check the passport number character by character. Thai passports have the letter and a number, then seven digits, and people commonly transpose two of them because they are reading from the visual inspection zone page rather than the identity page.
Use the official domain. The TDAC is free. Every other site charging you to file it is reselling something it does not have access to, and several of them are simply a form that mails your passport details somewhere you did not intend.
