How to Get a Thai Tax ID as an Expat (Step by Step)

A Thai Tax Identification Number (TIN) is free, takes under an hour, and unlocks filing, refunds and treaty relief. Here's exactly how.

What you need

Where to go

Any Revenue District Office (สรรพากร). Bangkok has 20+ districts; provinces have a central office. You don't strictly need your own district's office.

The process

  1. Request taxpayer registration form P.N.D.91 / ภ.พ.ด.91
  2. Fill in details; passport number serves as ID for foreigners
  3. Staff verify documents → your 10-digit TIN is issued on the spot
  4. Register for e-Filing at the same visit (or online later)

Total time: 20–60 minutes.

Why get one even if you owe nothing?

  1. The remittance era: since 2024 more expats have filing obligations than ever (explained here)
  2. Refunds: over-withheld employment tax requires a filed return + TIN
  3. Treaty relief claims require a TIN on documentation
  4. Banks/insurers increasingly request it during onboarding

Common gotchas

IssueNote
Name mismatchRegister EXACTLY as in passport; mismatches break e-Filing later
Moved addressUpdate at any district office when you relocate
Lost TINAny RD office retrieves it with your passport
Already registered?Ask staff to check before creating a duplicate
Have your TIN? Check whether you actually must file: Do I Need to File? → · Estimate: Tax Calculator →

Procedures as of August 2026; small variations between offices are normal.