How to Verify a Business Tax Number in Singapore

Verifying a business tax number in Singapore is essential to ensure you are dealing with a legitimate GST-registered business. A GST number, also called GSTIN, is issued by IRAS to businesses registered for Goods and Services Tax. This guide helps small business owners confirm the validity of a GST number to avoid errors in tax claims or payments.

Why this comes up / what goes wrong

Small business owners in Singapore often need to verify a GST number when dealing with new suppliers, clients, or partners. Incorrect GST numbers can lead to rejected GST claims or compliance issues. Sometimes, a business may quote a GST number that is inactive, invalid, or mistyped. Without proper verification, you risk filing inaccurate GST returns or losing input tax credits.

Step-by-step

1. Obtain the GST number from the business you want to verify. It should be a 9-digit number followed by "GST" (e.g., 123456789GST). Check the format carefully.
2. Check the format: The GST number must be exactly 9 digits followed by the letters "GST". No spaces or other characters are allowed.
3. Use the IRAS GST Registry: Visit the official IRAS GST Registry website (search "IRAS GST Registry" on your browser) to enter the GST number. The registry confirms if the number is valid and registered.
4. Confirm the business name: The registry will also show the registered business name linked to the GST number. Ensure it matches the business you are dealing with.
5. Keep a record: Save a screenshot or printout of the verification result for your records and audit purposes.
6. Cross-check invoices: When receiving GST invoices, verify the GST number on the invoice matches the verified number.

If you are unsure or want to automate some sales processes involving GST verification, consider using tools that integrate with your CRM system. For example, a WhatsApp and SMS CRM can help manage client communications while you verify business details separately. For sales teams, a built-in CRM dialer helps confirm client information efficiently.

Example (fictional figures)

A renovation contractor in Jurong receives a GST number from a new supplier: 201234567GST. They want to verify it before claiming input tax.

Step 1: Check format: 201234567GST has 9 digits + "GST" - correct.

Step 2: Visit IRAS GST Registry and enter 201234567GST.

Step 3: Registry shows the business name "Jurong Supplies Pte Ltd" matches the supplier.

Step 4: Contractor saves the verification screenshot dated 15/06/2024.

Step 5: On the invoice dated 10/06/2024, GST amount is S$8,640 on a supply of S$96,000.

Step 6: Calculate GST: S$96,000 × 9% (assumed GST rate) = S$8,640

The GST number is valid, so the contractor claims the input tax confidently.

Common mistakes

• Mistyping the GST number: Always double-check the 9 digits and the "GST" suffix. Prevent by copying the number directly or scanning QR codes if available.
• Assuming all 9-digit numbers with "GST" are valid: Use the IRAS GST Registry to confirm registration.
• Ignoring business name mismatch: If the registered name differs from the supplier’s, clarify before proceeding.
• Not saving verification evidence: Keep records for audit and compliance.
• Relying solely on invoices: Fake invoices can have invalid GST numbers; verification is essential.
• Delaying verification: Check GST numbers early in the supplier onboarding process to avoid delays.

Frequently asked questions

How can I find the official IRAS GST Registry? Search "IRAS GST Registry" online to find the official IRAS page where you can enter and verify GST numbers. Avoid third-party sites that may have outdated information.

Can I verify GST numbers via phone or email with IRAS? IRAS primarily provides the GST Registry online. For complex queries, you may contact IRAS directly, but verification is most efficient online.

What if a GST number is not found in the registry? If the GST number is not found, it means the business is either not registered for GST or the number is incorrect. Do not claim input tax from such suppliers.

Is the GST number the same as the UEN? No. The GST number is the Unique Entity Number (UEN) plus "GST" suffix and is only for GST-registered businesses. The UEN is the general business registration number.

Can I use HelloGrowthCRM to track GST numbers? While HelloGrowthCRM does not verify GST numbers automatically, it helps manage your sales leads and communications, including WhatsApp and SMS messaging, which can assist your sales team in keeping client records organised. Learn more about HelloGrowthCRM for Singapore and its WhatsApp and SMS CRM features.

Key takeaways

• Verify GST numbers using the official IRAS GST Registry website.
• Check the GST number format: 9 digits + "GST".
• Confirm the business name matches the GST number.
• Save verification evidence for compliance.
• Avoid relying only on invoices for GST verification.
• Verify GST numbers early to prevent tax claim issues.

Start verifying your business contacts’ GST numbers today to protect your tax claims and compliance. For managing your sales and client communications efficiently, consider HelloGrowthCRM’s solutions like the built-in CRM dialer and WhatsApp and SMS CRM features tailored for Singapore businesses.

Start on the Free Forever plan (200 leads, no credit card) at HelloGrowthCRM.

This article is general information, not tax or legal advice. Rules change; confirm the current position with IRAS or your accountant before acting.