Tax

Received a Thai tax assessment? Start here

Identify the notice, receipt date, appeal deadline and accounting evidence, and separate an appeal from a request to defer payment.

Prepared by Patinya Wongwitit Law OfficeUpdated
Tax

The short answer

Keep the notice and proof of receipt. Establish whether it is an information request, an assessment or an appeal decision: these documents serve different purposes. Do not wait for a complete accounting file before checking the deadline.

Identify the document before debating the amount

Mark the issuing office, reference, tax type, period and actual receipt date. List multiple notices separately; combining them into one total can obscure issues or deadlines.

A request for records and an assessment may concern the same period without being the same procedural step. Start with the wording and basis stated in the letter.

Appeal deadlines and payment are separate

Revenue Department guidance describes a general 30-day assessment-appeal period from receipt and explains that an appeal does not automatically defer payment. Check the specific notice, time calculation and filing channel.

If the date is close or has passed, disclose that immediately. An extension or payment deferral requires its own assessment under the relevant rules and approval; it should not be assumed.

Match records to the assessment reasons

List each disputed point and place supporting records alongside it. A large unindexed file is harder to assess than a document set tied to specific issues.

  • Assessment and delivery evidence
  • Relevant returns, VAT reports and ledgers
  • Contracts, tax invoices, bank records and reconciliations
  • Explanations and documents already given to officials

State what you need from the review

Explain whether you need a calculation review, grounds of challenge, appeal preparation or payment options. Include unfavourable facts so the response is not built on a partial record.

This is a preparation guide in the context of Revenue Department tax procedures, not a universal deadline for all taxes and agencies.

Common questions

Should I make contact before all accounts are ready?

Yes. Start with the notice and receipt date, then prioritise missing records.

Is payment relief the same as an appeal?

No. The purpose and requirements must be assessed separately.

Which document should I send first?

The complete notice, its receipt date and any stated deadline.

Patinya Wongwitit Law Office

Office principal: Patinya Wongwitit
Thai Barrister-at-Law · Industrial-engineering background

Background and qualifications

General information, not advice for a specific matter. Your facts and applicable law may differ. Check the actual documents and deadlines before acting.

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