TDAC Not Working? Fixes for Every Common Error (2026)
Something went wrong with your TDAC: the portal refuses your date, the page stops loading, the email never arrives, or you spotted a mistake after you submitted. This is the list of fixes: what each problem means, and the fastest way to solve it. Still filling in the form? Read the 10 common TDAC mistakes before you submit. For the whole process from start to finish, see the Thailand Digital Arrival Card guide.
Verified: October 28, 2026
Flight soon and the form won't cooperate?
"Arrival date not allowed": the 3-day window
The single most common 'error' isn't a bug: the TDAC only accepts submissions in the 3 days before your arrival date, or on the arrival day itself (see the exact dates). If your flight is five days out, the date is rejected by design. Prepare your details now, set a reminder, and file when the window opens. Nothing you click will open it early.
The site won't load or keeps timing out
The portal has outages and slow spells, often at busy hours. The official FAQ gives two fixes: after a 429 error, refresh the page and try again; after a 0 Unknown Error, check that you are connected to the internet. If that does not help, try a different browser or a private window, clear the site's cookies, switch between mobile data and Wi-Fi, or try again later. If you use a VPN, try again with it switched off.
No confirmation email, no QR code
Check spam and promotions folders and download the TDAC from the confirmation page if it is still open. If the email address is wrong, use Update Arrival Card before travel. If the record cannot be recovered or a restricted identity field is wrong, submit a new correct form; the latest valid submission is used.
The dropdowns defeat you: provinces, districts, postcodes
Thai accommodation addressing (province → district → sub-district → postcode) confuses everyone. Copy the exact fields from your hotel's booking confirmation; if the sub-district is missing, the hotel's website footer or a maps lookup of the hotel name shows it. 'Bangkok' the city is Krung Thep Maha Nakhon in some lists — same place.
You submitted, then spotted a mistake
Use Update Arrival Card before travel for permitted fields. Full name, passport number, nationality, and date of birth cannot be changed there; submit a new correct TDAC when one of those restricted fields is wrong. Then download and keep the updated or replacement QR document.
Group and family submissions misbehaving
The official portal supports a group submission of up to 10 travelers. Each traveler, including an infant, still receives an individual TDAC and QR code. Keep all passports ready, review every traveler before submitting, and download every document afterward.
When to stop fighting the form
If the portal has failed for hours and your flight is close, you have two honest options: keep retrying at quiet hours (early morning Thailand time is usually quietest), or hand it to an assisted filing service: people who complete and check the card for you and email you the TDAC with its QR code.
Find your failure in the table, then read only that row
Most people arrive here mid-problem with a flight to catch, so start with the symptom rather than the explanation.
| What you are seeing | What it actually means | What to do |
|---|---|---|
| The arrival date is refused | Your arrival is more than 3 days away | Nothing to fix. Come back inside the window |
| Endless spinner on submit | Portal load, not your data | Wait and retry off-peak, or switch network |
| Submitted, but no email | Often a mistyped address, or the email is in spam | Check spam; fix the address with Update Arrival Card, or refile |
| "Invalid passport number" | A character that is not what you think it is | Re-read for 0/O and 1/I against the passport |
| District or postcode will not accept | Thai addressing has a level you have skipped | Fill province, then district, then sub-district |
| Session ends halfway through a family | The form lost the sequence | Complete one person fully, then start the next |
| Card arrived with a typo on it | The submission was accepted, the data was wrong | Use Update Arrival Card; refile if the name, passport number, nationality or date of birth is wrong |
The failures that are not failures
The three-day filing window. The official form accepts an arrival date within the permitted window; a later date being unavailable is expected behavior, not a payment or browser problem.
The correction route. A submitted card is not automatically final. Use Update Arrival Card before travel for permitted fields. Full name, passport number, nationality, and date of birth are restricted, so submit a new correct form when one of those is wrong. The latest valid submission is used. See the official TDAC FAQ.
Getting a Thai address the form will accept
The address fields defeat more travellers than every other part of the portal put together, because Thai addressing has one more level than most countries and the form insists on all of them in order.
The hierarchy runs: province → district → sub-district → postal code. In Bangkok the words change but the shape does not — district is "khet", sub-district is "khwaeng".
A worked example, using a hotel on Sukhumvit Road:
| Field | Value | Where to find it |
|---|---|---|
| Province | Bangkok, listed as Krung Thep Maha Nakhon | The dropdown, under K as often as B |
| District (khet) | Watthana | The hotel's own address line |
| Sub-district (khwaeng) | Khlong Toei Nuea | Usually on the booking confirmation |
| Postal code | 10110 | Fills itself once the sub-district is right |
Three things that unstick this reliably:
- Take the address from the booking confirmation, not from memory. Hotel websites print the full Thai hierarchy in the footer; booking sites often abbreviate it.
- If the postal code will not fill, the sub-district is wrong. They are linked, so the code is the symptom and the sub-district is the cause.
- Staying with friends? Ask them for the district and sub-district specifically. "The house on Soi 11" is not an answer the form has a field for.
Email problems, in the order they actually happen
- Check spam and promotions folders and search for TDAC.
- If the submission confirmation is still open, download the TDAC/QR directly.
- If the email address was entered incorrectly, use Update Arrival Card before travel and save the updated document.
- If you cannot recover the record, submit a new correct form with an email inbox you can access.
The official portal provides the TDAC after submission and by email; printing is optional. These paths are described in the official TDAC FAQ.
With hours to go: what is still worth trying
| Time to your flight | What is still sensible |
|---|---|
| More than 24 hours | Retry at a quiet hour — early morning Thailand time is the calmest the portal gets |
| 6 to 24 hours | Retry once on a different network and browser, then stop experimenting and get it filed by someone |
| Under 6 hours | Have it filed, or file on your phone at the departure gate and save the QR code offline immediately |
| Already flying | File on arrival-hall Wi-Fi or at a kiosk before joining the immigration queue |
When to update and when to submit again
Use Update Arrival Card for permitted changes before entering Thailand. The official update flow does not change full name, passport number, nationality, or date of birth. If one of those restricted identity fields is wrong—or the existing record cannot be recovered—submit a new accurate form and keep its TDAC/QR.
Download the document after submission or from the email, save it offline, and print a copy if that is safer for your trip. The official TDAC FAQ confirms both the correction rules and document options.
Many portal problems start as data mistakes. The field-by-field TDAC form guide prevents most of them before they happen.
Sources checked
- Immigration Bureau: TDAC FAQ · October 28, 2026
- Immigration Bureau: TDAC user manual · October 28, 2026
