Register for VAT early vs waiting for the threshold
Quick answer
A business whose income from goods or services passes 1.8 million baht a year must apply to register for VAT within the period set by the Revenue Code. Below that, registering is optional. Businesses with heavy input tax, or selling to counterparties who need tax invoices, usually gain from registering early. Businesses selling to consumers with little input tax carry a lighter monthly filing load by waiting.
Side-by-side facts
| Aspect | Voluntary VAT registration from day one | Wait until turnover reaches the compulsory level |
|---|---|---|
| Legal trigger | You may opt in before the threshold | Application becomes mandatory once income reaches the level |
| Input tax | Claimable where the tax invoice is valid | Input tax stays buried in cost of goods |
| Monthly workload | Monthly return plus purchase and sales reports | No monthly VAT return yet |
| How counterparties see you | Large counterparties open accounts more readily | Some buyers ask for extra paperwork before ordering |
| Consumer pricing | Tax is added to the sale price, tightening price competition | More pricing flexibility in consumer markets |
| Risk of missing the trigger | Not applicable — already registered | Surcharges and penalties apply under the Revenue Code |
Choose Voluntary VAT registration from day one when
- You buy machinery, materials or leases carrying heavy input tax in year one
- Your main customers are companies that request a tax invoice every time
- You expect turnover to cross the threshold inside a single year
- You want the document system settled before volume grows
Choose Wait until turnover reaches the compulsory level when
- You sell direct to consumers and compete on shelf price
- Your main cost is labour, which carries no input tax
- The team is small and not ready for a monthly filing rhythm
- Income is well below the trigger and predictable
Documents to prepare
- Company affidavit, or the ID card of an individual operator
- Proof of the right to use the premises, such as a lease or a consent letter
- Location map plus photographs of the signage and building
- An income estimate and a description of the activity actually carried on
- Power of attorney with duty stamp if someone files on your behalf
Step by step
1. Map income and cost structure
Separate which income falls within the VAT net and which costs come with usable tax invoices. Those two figures decide the answer.
Typical duration: 1–3 days
2. Model both routes in cash terms
Compute after-tax profit for both routes over the next twelve months, including paperwork cost and team time.
Typical duration: 2–4 days
3. Make the premises inspectable
Put up clear signage, keep the workspace consistent with what you declare, and hold complete proof of occupancy before filing.
Typical duration: 3–7 days
4. File the application and receive registration
Submit the application with supporting documents to the Revenue Department. Timing depends on completeness and any premises check.
Typical duration: Depends on the office
5. Start a monthly rhythm that holds
Set the tax invoice format, numbering, purchase and sales reports, and a filing calendar with a named owner at each step.
Typical duration: Ongoing
What usually goes wrong
- Counting only bank deposits as income and so missing the point where filing becomes due
- Issuing tax invoices before the registration number is granted
- Keeping input tax invoices with incomplete particulars and then claiming them
- Moving premises without notifying the change of registered particulars
- Skipping the purchase and sales reports in a month with no transactions
Why an adviser beats a template
This question does not end at a threshold figure; it ends with the tax structure the business will live in for the next three to five years. We weigh it against branch plans, hiring plans and the contracts about to be signed, rather than simply answering whether the number has been passed. Our team has run tax cycles for businesses of every size for over fifteen years, and keeps advising after registration — the certificate is not where our work stops.
Frequently asked questions
Can voluntary registration be cancelled later?
Leaving the system has statutory conditions and is not always available on request. Treat registering as a long-term decision, not an experiment.
Is income counted per channel or in total?
It is the operator's total income, not a per-channel figure. Several online shops under one owner are added together.
Can an individual register?
Yes — individuals fall within the same rules as companies. The supporting documents differ: an ID card instead of a company affidavit.
What if the threshold was passed months ago?
Compile the full back-period sales first, then discuss the catch-up route. Filing in a hurry without firm figures usually means correcting twice.
Does it affect withholding tax?
They are separate duties. Withholding depends on the type of payment made; VAT depends on the supply. Both must be run in parallel.
We would rather not run the monthly work ourselves
We take it from the timing analysis, through documents and premises, the application, the invoice design, then the monthly returns and reports with a summary written for management.
Official sources
Not sure which route fits your case?
Call +66-92-017-0000, email contact@tla.co.th, or message us on LINE. Monday to Saturday, 09:00–18:00 Bangkok time, in English or Thai.