Bangkok, Thailand – October 22, 2026 – PRESSADVANTAGE –
Siam Legal International, a full-service law firm with more than 22 years of experience in Thailand, has released a guide to THIM, the official app of Thailand’s Immigration Bureau, following its official launch after a pilot phase that began in late May. The app has recorded more than 600,000 downloads, a sign that travelers are beginning to trust the platform, and the launch came with a clearer list of services the bureau plans to add.
The Immigration Bureau, which sits under the Royal Thai Police, introduced the app to simplify paperwork for arriving travelers and foreign residents. THIM is free on the App Store, Google Play, and Huawei AppGallery. Its main function at present is filing the Thailand Digital Arrival Card (TDAC).
To file, the app scans the user’s passport, including the chip if the phone supports NFC, then runs a liveness check and a facial comparison to confirm the user’s identity. One person can file for up to 10 travelers, and the profile is saved, so later trips only require flight, accommodation, and date details. According to the bureau, first-time registration takes under three minutes, repeat filings take under one minute, and trip details can be updated if plans change.
THIM does not grant permission to enter or stay in Thailand, which is still determined by the traveler’s visa or visa exemption. The app handles arrival paperwork only. It also includes an Explore Thailand section where users can find special privileges and offers from participating partners.
Every foreign national must file a TDAC each time they enter Thailand, including long-term Thai visa holders and residents. In THIM, trip details can be entered early, but the card can only be submitted within 72 hours before arrival. Entering details early does not file the card, which only counts once it is submitted within that window and a confirmation QR code is received.
The app is optional. The same arrival card can be filed for free on the official website at tdac.immigration.go.th, and the TDAC never costs anything through either route, so any website requesting payment is not the official one.
“THIM is a convenience, not a requirement, and that distinction matters,” said Rex Baay, Senior Immigration Consultant and Operations Manager at Siam Legal International. “The arrival card is mandatory, but the app is simply one way to file it. For frequent travelers, long-stay residents, and families filing together, saving passport and personal details means each new entry only needs flight, accommodation, and dates, which saves real time on every trip.”
The official launch also set out services the bureau plans to bring into the app, including 90-day reporting, visa extensions, visa on arrival, document requests, appointment booking with immigration officers, and submitting documents online in advance. None of these services has a launch date yet. Until they arrive, THIM does not replace visa applications, extensions, or 90-day reporting.
The guide identifies several common mistakes that can cause delays at the immigration counter. Name mismatches are the first, as a single wrong character can cause problems, so names must match the passport exactly. Unfinished submissions are another, with travelers entering their details early in THIM and then never completing the final step inside the 72-hour window.
Failed scans are a further issue, and if the app cannot read a passport, travelers should use the official website instead. Saving a screenshot of the QR code as a backup ensures there is always proof of filing. Siam Legal’s THIM app guide covers each of these points in detail.
Strictly speaking, travelers do not need to download THIM, as the arrival card is required but the app is not, and the official website does the same job. For those who enter Thailand often, however, the app removes the need to fill in the whole arrival card from scratch on every trip. Once 90-day reporting and visa extensions become available in the app, it is expected to become even more useful for anyone living in Thailand.
Siam Legal International is a full-service law firm with more than 22 years of experience assisting foreign nationals in Thailand, with offices in Bangkok, Chiang Mai, Phuket, and Pattaya. The firm provides comprehensive legal support across immigration, property transactions, business law, family law, and litigation.
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For more information about Siam Legal International, contact the company here:
Siam Legal International
Rex Baay
+662 254 8900
info@siam-legal.com
18th Floor, Unit 1806 Two Pacific Place,
142 Sukhumvit Rd, Khlong Toei,
Bangkok 10110, Thailand
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