How to Fill In the TDAC, Field by Field (2026)

Have every passport, the local arrival date, final transport details, the first night's full Thai address, recent travel history, and a working email address ready. The official portal supports individual and group submission for up to 10 travelers, but every traveler still receives an individual TDAC.

Review each traveler on the preview screen before submitting. After submission, permitted details can be changed with Update Arrival Card; full name, passport number, nationality, and date of birth require a new correct submission. See the official TDAC manual and FAQ.

Printable TDAC checklist: everything the form asks for, on one page.

Almost every card that cannot be found at the desk comes down to one thing: what was typed does not match what the passport says. The fix is to stop reading the tidy part of the photo page and read the machine-readable zone instead — the two lines of capital letters and chevrons across the very bottom. That zone is what the scanner reads, so it is the version of your identity that has to match.

A specimen first line looks like this:

P<GBRSMITH<<JOHN<MICHAEL<<<<<<<<<<<<<<<<<<<<

Read it as: document type P, issuing country GBR, family name SMITH, then a double chevron, then the given names JOHN MICHAEL separated by single chevrons. The chevrons are padding — type spaces, or nothing at all, never the chevron character itself.

Three rules follow from that, and between them they settle most name questions:

The system accepts a card only in the 3 days before your arrival date, or on the arrival day itself (see the exact dates). Not before — and being early is not a virtue here, because it is not possible. This is the timing that actually works:

The window is measured against your arrival in Thailand, not your departure. Leaving Sydney on Friday evening to land Saturday morning means you can file from Wednesday.

This is the part that catches people out. The window counts calendar days, not hours, and it follows your arrival date in Thailand: not your departure date, and not the date where you are when you file.

Say you land in Bangkok on a Tuesday. You can submit on the Saturday, Sunday, Monday or Tuesday. For every day of the week:

The practical version: take your landing date in Thailand, count back three days on a calendar, and set a reminder for that day. On an overnight flight the landing date is often the day after you leave. Or let the calculator count for you.

This is the table worth reading twice. On the left is what you typed; on the right is what happens at the desk in Bangkok.

Abstract advice is easy to nod along to and hard to apply. So here is an entire card, filled in for an invented traveller, with the reasoning beside each answer.

Our traveller: Maria de la Cruz Santos, Spanish passport, flying Madrid to Bangkok overnight on 14 March, landing on the 15th, three nights at a hotel in Bangkok then onward to Chiang Mai, changed planes in Doha.

Three things about that table are worth pulling out.

Chiang Mai never appears. The form asks where you sleep on night one. The rest of the itinerary is not its business, and volunteering it creates mismatches to explain later.

Qatar appears. The fourteen-day question is a health-screening question, and a layover where you passed through immigration counts. A layover spent entirely airside does not.

The second given name appears. She has never written "Santos" on anything in her life. Her passport's machine-readable zone has it, so the card has it.

Families. One card each. Adults complete their own, a parent completes a child's, including a newborn's. A single submission can carry up to 10 travellers, so you can do the household in one sitting — but it produces one card per person, never one card for the family. There is enough to this one that it has its own section below.

Transit. Land in Thailand and pass through Thai immigration — even only to collect and re-check a bag — and you need a card. Stay airside on a single through-ticket without clearing immigration and you do not. When it is genuinely unclear, file: an unused card costs nothing.

Land and sea arrivals. This is an entry requirement, not an airport requirement. Crossing from Malaysia at Sadao, from Laos over the Friendship Bridge, or arriving by ferry, you still need one. There is no flight number to give, so name the crossing point or the vessel in the transport field.

Dual nationals. Use the passport you will actually hand to the Thai officer, and use it consistently — the same document for the airline, the card and immigration. Mixing two passports across those three points is the fastest route into a long conversation.

Trips booked far ahead. Book the trip now, file the card inside the window. And if you change hotels on day three, the form still only wants night one.

The rule is one card per person, and every consequence of that surprises somebody.

What actually goes wrong. Not the rule itself, which people accept quickly. It is the session. The group flow is supported, but it holds everyone's data in one unsaved form, so a timeout on traveller four takes travellers one to three with it. Have every passport in front of you before you start, and if the session drops twice, file each person as their own submission — the result is identical.

Before you start a family filing, write out each traveller's details somewhere you can copy from: name exactly as the machine-readable zone has it, passport number, date of birth, nationality. Six people means six sets of details, and doing it from six passports in your lap is where a digit gets transposed.

Carrying six codes. One printed sheet per family, each code labelled with a name, kept with whichever adult carries the passports — plus every code saved to a phone. Children's cards belong with a parent, not on a child's own phone.

The money. The government portal charges nothing for anyone, at any age. Paid services price per traveller, and that is where a family's costs multiply — which is worth checking carefully before you start, since some services (ours included) charge less for each additional person and some do not.

Download the TDAC document and QR code as soon as the confirmation appears. The official system also sends it to the email address supplied, and the document can be shown on a phone or printed as a backup.

If something is wrong, use Update Arrival Card before travel for fields the portal permits. Full name, passport number, nationality, and date of birth are restricted; submit a new correct form if one of those fields is wrong. The latest valid submission is used. These correction and download paths are documented in the official TDAC FAQ.

The government portal is free and, with straightforward details, perfectly usable. Set a reminder for 3 days before your landing date, gather the list above, and give yourself fifteen unhurried minutes.

Assisted filing buys three specific things, and they are worth naming precisely rather than vaguely: somebody checks the fields most likely to be wrong before submission, the card goes in inside the window without you having to remember, and the questions are asked in your own language. Travelling alone with a simple passport and a hotel booking, you may need none of that. Filing for a family of five, from a country whose alphabet is not Latin, three days before you fly, it is a different calculation.

Want to see where other travelers go wrong? Read the 10 most common TDAC mistakes before you hit submit.