Quick Answer
Thai customs valuation usually starts with transaction value, then moves to alternative methods only when needed; duty and VAT are calculated from the final accepted customs value.
This guide focuses on how Thai customs valuation is evidenced in practice, and why document consistency determines whether transaction value is accepted.
Landed Cost Breakdown
Why does valuation evidence trigger reassessment?
Reassessment typically starts when invoice, payment, freight, and assist values do not reconcile cleanly to the declared customs value.
- Weak transaction value support.
- Invoice-payment mismatch.
- Missing notes for freight or assists.
- Late evidence submission.
What should you prepare before filing to support declared value?
Prepare a valuation worksheet that maps each declared component to source documents before submission.
- Reconcile invoice and payment records.
- Keep valuation worksheet.
- Coordinate valuation with classification.
- Archive evidence for audit.
What evidence format helps valuation review close faster?
Reply with reconciled records that clearly connect invoice lines, transfer references, freight terms, and declared additions.
- Provide invoice, payment transfer, and currency records together.
- Reconcile freight, insurance, assists, and discounts in one worksheet.
- Explain special terms such as rebates or related-party pricing.
- Attach contracts or purchase orders supporting declared value.
How do you keep valuation files audit-ready over time?
Version-control valuation packs by supplier and lane so repeat imports use proven evidence structures.
How should you communicate valuation uncertainty to buyers?
State that final duty/VAT remains provisional until valuation acceptance, and explain which documents can still change the base.
- Label duty/VAT estimates as provisional until valuation acceptance.
- Explain which valuation component is under review.
- Share document request deadlines and ownership clearly.
- Issue revised landed-cost numbers only after authority acceptance.
Case example: transaction value accepted after reconciliation
A parts importer declared transaction value but could not immediately provide aligned payment records. Customs review expanded until supporting evidence was submitted, illustrating how valuation outcomes depend on documentation quality.