Oxaide Research • 1 Oct 2026
GST registration check: how to verify any Singapore supplier
Before you pay an invoice with GST on it, confirm the supplier is actually GST-registered. The check is free, takes two minutes, and decides whether your input tax claim survives. This walkthrough covers the exact steps, what each result means, the name-mismatch traps that waste the lookup, and when to order the S$49 cited check instead.
Check GST registration in 4 steps
- Copy the UEN from the quotation or invoice. Not the shop name, not the website brand. The UEN is the single identifier across ACRA, IRAS and corporate PayNow.
- Confirm the registered name behind that UEN on ACRA BizFile (free, no account), or our free UEN lookup. Write down the exact legal name; trading names differ constantly.
- Run the IRAS GST-registered-business search by business name. The register returns registered or not, with effective dates. It is free and needs no login.
- Match three names: the GST register entry, the ACRA registered name, and the bank payee. All three must agree. Any mismatch is a stop-and-ask, not a pay-and-hope.
Shortcut: our free GST checker walks the same name-then-register sequence in one page. Use either; never skip the match step.
What each result means for your money
| Result | What it means | Buyer action |
|---|---|---|
| Registered, dates cover invoice | Supplier may charge GST at the prevailing rate and issue a valid tax invoice | Pay on normal terms; keep the tax invoice for input tax |
| Registered, invoice predates registration | GST on that invoice was charged before the supplier could charge it | Query in writing; do not claim input tax on that invoice |
| Not registered, no GST on invoice | Normal for smaller suppliers below the threshold; nothing to claim | Pay the net amount; no input tax either way |
| Not registered, GST on invoice | Red flag. Wrong entity searched, stale template, or unlawful charge | Stop. Reconfirm the exact UEN, then query the supplier in writing |
| Name matches nothing on IRAS | Usually a trading name, typo, or the wrong entity entirely | Go back to the UEN on BizFile; never pay an unmatchable name |
The 3 GST-check mistakes that cost money
- Searching IRAS by trading name and stopping at no-hit. The register keys off legal names. A no-hit on a shop name proves nothing; confirm the UEN on BizFile first, then search the legal name.
- Trusting the GST line on the invoice. Templates lie. Old ones survive deregistration; dishonest ones add GST that was never due. The register is authoritative, the invoice is a claim. Check the claim.
- Treating registered as a clean bill of health. Registration proves IRAS-system membership, not solvency, honest officers, or a matching payee. Standing, charges, filings and the payee match are separate checks. See below.
After the free check. What next?
- Name mismatch or unclear result? Read the BizFile walkthrough and redo the UEN-to-name step. Most GST mysteries are identity errors.
- Need the one-minute version? How to know if a company is GST registered is the fastest register search. Paying a vendor invoice? Verify the supplier before you pay covers invoice red flags.
- Paying a deposit to this supplier? Follow the full legitimacy routine. Status, charges, reviews, staged payments.
- Want registration, standing and invoice match read together? The S$49 GST check workflow delivers one cited file in about 5 minutes.
- Bigger exposure or odd payment instructions? Use the pre-deal check workflow instead and review pricing first.
Frequently asked questions about GST registration checks
How do I check if a company is GST registered?
Confirm the UEN and legal name on BizFile, then run the free IRAS register search by business name. Registered or not, plus effective dates. Our free GST checker walks both steps.
Is the GST registration check free?
Yes, both halves. The IRAS search and the ACRA name check cost nothing. The S$49 check is for when you want it read and cited for the file.
What if my supplier charges GST but is not registered?
Stop and query in writing. Only registered businesses may charge GST; your input tax claim on that invoice fails. Usually a wrong-entity search or a stale template. Sometimes worse.
Does GST registration prove a company is legitimate?
No. It proves IRAS-system membership, generally past S$1M taxable turnover or voluntary. Solvency, officers and payee match are separate checks.
Can I claim input tax if the supplier is not GST registered?
No. Claims need a valid tax invoice from a registered supplier. Check before you pay, not at filing time.
Research, not tax advice. Portal flow per IRAS published guidance; confirm specifics on the IRAS register before acting. What a result means for your invoice is between you and your accountant.