How to Check Numbers Against Singapore's DNC Registry

How do you check numbers against the Do Not Call Registry?

You check them on the DNC Registry portal at dnc.gov.sg, which the Personal Data Protection Commission (PDPC) website links to for organisations. A Singapore-registered organisation applies for a main account using its UEN and a representative's CorpPass, and can add sub-accounts if several people or teams need to check numbers.

The portal offers two ways to check. Small Number Lookup takes up to 10 telephone numbers at a time and shows the results straight away. Bulk Filtering takes a CSV file with a single column of 8-digit numbers, with no stated cap on how many, and the results come back within 24 hours. The portal accepts only 8-digit numbers that start with 3, 6, 8 or 9.

Each number is checked against the No Voice Call, No Text Message and No Fax Message Registers, and checking is charged per number. Read the current fees on the portal when you sign up.

How long is a Do Not Call check result valid?

A result is valid for 21 days. The PDPC's page on checking numbers refers to this as the 21-day DNC check validity, and tells organisations to note the validity period and fees before they check.

In practice, count 21 days from the date you receive the result. If your calling campaign runs longer than that, or you only start calling a month after the check, check the list again.

This matters for lists that sit in a spreadsheet for weeks. Date the file when you receive the results, and keep the original result file with it.

Do business-to-business calls need a Registry check?

Generally no, when the call is to an organisation for that organisation's own purposes. The Do Not Call Registry site states that telemarketing calls or messages of a commercial nature that target other businesses are excluded from the Do Not Call provisions.

That protection is lost once the call is about the person's own needs. A call to a director about the company's accounting software is a business call. A call to the same director about their personal insurance or their own savings is aimed at an individual, and the Registry rules apply.

This is general information, not legal advice. For your own list and your own pitch, read the PDPC Advisory Guidelines on the Do Not Call Provisions and the Personal Data Protection Act 2012, and ask a lawyer if the case is not clear.

What should you do before handing a list to a calling service?

Check the list yourself, keep the result file, and make sure the check is still inside the 21 days when calls begin.

Greetsby works this way. The client checks their list against the Registry before sending it, and confirms that they have done so when they upload it. Greetsby does not run the check for clients. If anyone on the list asks not to be called again, they are not called again, and Greetsby passes the request on to the client so it can be recorded.

A simple routine: export the list, remove any numbers that are not 8 digits starting with 3, 6, 8 or 9, upload the CSV for bulk filtering, wait for the result, then send only the numbers the result file allows. Save the results file with its date.

What should you keep on record?

Keep the dated result file for each check, the list you actually called, and a record of anyone who asked to be removed. If a question comes up later, you can show when you checked and which numbers were clear.

Moneylenders should note that unsolicited calls by moneylenders have been banned since 1 April 2025, so a clean Registry check does not make those calls permitted.

The checks themselves are made on dnc.gov.sg, and doing it there yourself keeps the result in your own account.

Questions

Sources

• PDPC: Check numbers against Do Not Call (DNC) Registry
• Do Not Call Registry: Information for consumers and exclusions
• Do Not Call Registry: Business rules for organisations

General information for businesses in Singapore, not legal advice.