Singapore's Do Not Call Registry, explained properly
The Do Not Call Registry is a national list under the Personal Data Protection Act that lets people in Singapore opt out of marketing messages on their phone numbers. If your business makes marketing calls to Singapore numbers, you must check the relevant register first, unless a specific exemption applies. A check result is valid for 21 days.
Most pages on this topic are written by telemarketing vendors and get at least one important detail wrong. This one sets out what the rules actually say, where the common misunderstandings are, and what changes when an AI voice agent is doing the dialling. Sources are listed at the bottom with the dates they were checked.
Looking to stop marketing calls to your own number? You can register your Singapore number on the Do Not Call Registry yourself, free, through the official PDPC channels. Registration does not expire. The rest of this page is written for businesses that need to comply.
The obligations, in order
1. There are three registers, not one
The Registry is split by channel, and checking one does not cover the others. If you both call and text the same list, you must check both registers.
| Register | Covers |
|---|---|
| No Voice Call | Marketing phone calls. This is the one that matters for AI calling. |
| No Text Message | Marketing SMS and MMS. |
| No Fax Message | Marketing faxes. |
2. Check before you send, and re-check every 21 days
The prescribed duration for a Do Not Call check is 21 days. Screen the list, and if you are still working it three weeks later, screen it again before you continue.
You may still see pages describing a 30 day or 60 day validity. Those reflect the arrangements when the Registry first launched and are out of date. Work to 21 days.
3. Only certain numbers can be checked
The Registry accepts 8-digit Singapore numbers beginning with 3, 6, 8 or 9. Numbers outside that format cannot be screened, which does not mean they can be called freely. It means you need another basis for contacting them.
4. Do not conceal who is calling
The caller's identity must not be concealed. For an AI voice agent this is worth thinking about properly: the opening line should make clear which organisation is calling.
5. Honour opt-outs within 21 days
When someone asks to stop receiving your marketing messages, you have 21 days to make that effective. In practice, for an automated dialler working a list continuously, 21 days is far too slow to rely on. Opt-outs should reach your suppression list immediately.
6. The penalties are not nominal
Financial penalties for breaching the Do Not Call provisions are up to S$1 million for an organisation, or S$200,000 for an individual. These are flat caps. The turnover-based penalty of up to 10% of annual Singapore turnover that is often quoted applies to the data protection provisions, not the Do Not Call provisions. It can still reach you, because how you obtained and stored the list falls under those provisions.
The exemption most businesses get wrong
The "ongoing relationship" exemption does not cover voice calls. It comes from the Text and Fax Exemption Order, and as the name says, it applies to text and fax messages only. Having an existing customer relationship does not by itself let you make a marketing call to a number on the No Voice Call register.
This matters because the exemption is widely cited in Singapore marketing content without the channel restriction attached. An insurance agency with thousands of existing policyholders, or a property agency with a database of past clients, can reasonably conclude it is free to call them. For text messages, subject to the conditions, often yes. For voice calls, no.
| Basis for contact | Voice calls | Text and fax |
|---|---|---|
| Clear and unambiguous consent, evidenced in written or other form | Applies | Applies |
| Ongoing relationship with the subscriber | Does not apply | Applies, subject to conditions including opt-out |
| Message sent to an organisation's number for a business purpose | Outside scope | Outside scope |
What counts as consent
The standard is clear and unambiguous, and it must be evidenced in written or other form. A pre-ticked box is not consent. A general "we may contact you" buried in terms is not consent for this purpose. Someone completing a form asking you to call them about a specific service is.
Keep the evidence. If you are ever asked to justify a call, the question will be what the person agreed to and when, and a database field saying "consented" with no record behind it is not much of an answer.
Other messages outside scope
Some messages are not marketing at all and therefore sit outside the Do Not Call provisions: confirming a transaction the person entered into, delivery or warranty information, service and account notifications, market research or surveys that do not sell anything, and messages for charitable, religious or similar purposes. If your call has a marketing purpose attached to it, though, do not assume the wrapper protects it.
Calling hours: industry practice, not law
Singapore law does not prescribe the hours during which telemarketing calls may be made. Nothing in the PDPA, the Do Not Call provisions or the PDPC's advisory guidelines sets a permitted window. Plenty of pages online imply otherwise, usually without a source.
What does exist is a well-established industry standard, from the Contact Centre Association of Singapore's telemarketing guidelines:
| Day | Accepted calling window |
|---|---|
| Monday to Friday | 8:00am to 9:00pm |
| Saturday | 9:00am to 6:00pm |
| Sunday | No calls |
| Public holidays | No calls |
Following these is expected practice and protects your brand, but the legally binding requirement is the Do Not Call check, not the clock. Sector rules may add their own constraints, so financial advisers and insurance representatives should check with compliance.
There is a planning consequence too. Six calling days a week, minus public holidays, leaves roughly 25 to 26 calling days a month, and only eight or nine hours a day when people realistically answer. Any monthly projection built on 30 days is wrong before it starts. See how that affects cost.
What changes when an AI makes the call
Legally, nothing. The obligation sits with the organisation on whose behalf the call is made. Using a vendor's platform does not move responsibility onto the vendor, and "the AI did it" is not a defence.
Operationally, quite a lot changes, and not in your favour:
- Speed multiplies mistakes. A human team calling an unscreened list makes a handful of breaches before someone notices. An AI voice agent running several concurrent lines makes hundreds.
- Opt-outs must be captured mid-conversation. A person hearing "take me off your list" writes it down. An AI voice agent only records it if it was built to recognise the request in the words the caller actually used, including in Mandarin or Malay.
- Suppression must be immediate. If the opt-out only applies at the end of a campaign, the same person can be called again tomorrow.
- Re-screening has to be scheduled. Twenty-one days passes quickly on a long campaign. This should be automatic, not a diary reminder.
- Disclosure is a live question. There is no specific Singapore rule at present requiring you to announce that a caller is an AI. Concealing it is a reputational risk that outweighs any benefit, and expectations here are moving.
A workable pre-call checklist
- Establish, for each record, whether you hold clear and unambiguous consent, and keep the evidence.
- Screen everything else against the No Voice Call register.
- Remove registered numbers and log the screening date.
- Load only the screened list into the dialler, never the raw list.
- Schedule re-screening before day 21.
- Confirm the agent captures opt-outs in every language it speaks, and that suppression is immediate.
- Restrict dialling to the accepted hours, in Singapore time.
- Make sure the opening line identifies your organisation.
- Keep recordings and screening logs long enough to answer a complaint.
Ask any provider these three questions. Does the platform screen against the No Voice Call register before dialling? Can re-screening be scheduled automatically on a 21-day cycle? How are opt-outs captured and how quickly do they take effect? A provider who cannot answer all three clearly is leaving the compliance work with you.
Six mistakes we see repeatedly
Treating existing customers as fair game for calls
The ongoing relationship exemption is text and fax only. For voice you need consent or a clean check.
Screening once at the start of a campaign
A check lasts 21 days, so a three month campaign needs screening five times, not once.
Assuming a purchased list is compliant
Consent obtained by someone else, for something else, is unlikely to be consent for your call. Screen it and keep the evidence.
Checking one register
Voice, text and fax are separate. A clean voice check says nothing about texting the same person.
Assuming the vendor is responsible
The obligation follows the organisation the call is made for. Contracts can allocate cost and blame, not the legal duty.
Believing calling hours are law
They are an industry standard worth following, but the enforceable requirement is the screening.
Common questions
What is Singapore's Do Not Call Registry?
How long is a Do Not Call check valid for?
Does the ongoing relationship exemption cover voice calls?
Do I need to check the Registry for B2B calls?
Does using an AI voice agent change my obligations?
Must I tell people they are speaking to an AI?
What if someone asks to be removed during the call?
What hours can telemarketing calls be made?
Sources
Checked 4 August 2026. Rules change, so verify before relying on any of this.
- PDPC, Advisory Guidelines on the Do Not Call Provisions. The 21-day prescribed duration, consent standard, and sender identification requirements.
- PDPC, Do Not Call Registry and Your Business. Obligations overview and opt-out handling.
- DNC Registry, business rules. The three registers and accepted number formats. Note this page still describes older check validity periods.
- Singapore Law Gazette, "The Singapore Do Not Call Register and the Text and Fax Exemption Order". Confirms the ongoing relationship exemption applies to text and fax, not voice.
- SingaporeLegalAdvice, Do Not Call Registry. B2B scope.
- Allen & Gledhill, increased maximum financial penalties under the PDPA from 1 October 2022. Confirms that the Do Not Call provisions (Part 9) carry flat caps of S$1 million for an organisation and S$200,000 for an individual, while the turnover-based penalty applies to the data protection provisions.
- Contact Centre Association of Singapore, Personal Data Protection and Telemarketing Guidelines. The calling hours standard. The association's public resource page was unavailable at the time of writing, so this is cited from secondary sources pending the primary document.
This is general information, not legal advice. It does not account for your specific circumstances, your sector's rules, or changes made after the date above. Get advice from a Singapore-qualified lawyer before relying on it for a live campaign.
Related reading
Is AI cold calling legal in Singapore?
Consent, disclosure, call recording and where law ends and industry practice begins.
Read guideAI calling for insurance agents
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