Complete Guide to Singapore's Do Not Call (DNC) Registry for Businesses

If your business sends marketing messages to Singapore phone numbers — whether voice calls, SMS, or fax — you are legally required to check the Do Not Call (DNC) Registry before every campaign. Failing to do so is a breach of the PDPA that can result in financial penalties of up to S$1 million.

The DNC Registry is one of the most frequently breached aspects of Singapore's data protection framework. Many businesses, particularly smaller ones, are either unaware of the requirement or assume it only applies to large marketing operations. It applies to everyone.

This guide covers everything you need to know to stay compliant.

What Is the DNC Registry?

The DNC Registry is a national database maintained by the Personal Data Protection Commission (PDPC) under Part IX of the PDPA. Singapore residents can register their telephone numbers to opt out of receiving unsolicited marketing messages.

There are three separate registers:

1. No Voice Call Register — Opt out of marketing voice calls
2. No Text Message Register — Opt out of marketing SMS/text messages
3. No Fax Message Register — Opt out of marketing fax messages

Individuals can register on one, two, or all three registers. Your obligation is to check the relevant register before sending each type of marketing message.

Who Must Comply

Every organisation that sends marketing messages to Singapore telephone numbers must comply. This includes:

• Companies (Pte Ltd, LLP, sole proprietors)
• Freelancers and self-employed persons
• Non-profit organisations conducting marketing
• Overseas companies marketing to Singapore numbers

There is no exemption based on business size, revenue, or the number of messages sent. Even a single unsolicited marketing message to a registered number is a breach.

What Counts as a "Marketing Message"

A message is considered a marketing message if its primary purpose is to offer, advertise, or promote goods, services, business opportunities, or investment opportunities.

Examples of Marketing Messages

• Promotional SMS about a sale or discount
• Cold calls offering products or services
• Fax advertisements
• Appointment reminders that include promotional offers
• Loyalty programme messages promoting new products

What Is NOT a Marketing Message

• Transactional messages (order confirmations, delivery updates, payment receipts)
• Service notifications (appointment reminders without promotional content, account alerts)
• Informational messages required by law or regulation
• Messages sent in response to the recipient's request or enquiry
• Messages from government agencies

Grey area: Messages that mix transactional and promotional content may be classified as marketing messages. If your appointment reminder includes "and enjoy 20% off your next visit," the entire message may be treated as marketing.

How to Check the DNC Registry

Step 1: Register for an Account

Create an account on the DNC Registry portal at dnc.pdpc.gov.sg. You will need your Corppass credentials.

Step 2: Prepare Your Number List

Compile the list of Singapore telephone numbers you intend to send marketing messages to. Numbers must be in standard Singapore format (8 digits).

Step 3: Submit a Check

Upload your number list to the DNC portal. The system will check each number against the relevant register (voice, SMS, or fax) and return results indicating which numbers are registered.

Step 4: Remove Registered Numbers

Remove all registered numbers from your marketing list. You must not send marketing messages to these numbers unless you have clear and unambiguous consent.

Step 5: Document Your Check

Keep a record of:

• The date of the check
• The numbers checked
• The results
• Which register(s) you checked

This documentation is your evidence of compliance if the PDPC investigates.

Timing Requirements

• Checks must be performed within 30 days before sending the marketing message
• If more than 30 days have passed, you must check again
• Best practice: check immediately before each campaign

Checking Fees

The PDPC charges a fee for DNC checks based on volume:

For most SMEs, the free web interface is sufficient for small campaigns.

The Consent Exception

You can send marketing messages to numbers on the DNC Registry if you have clear and unambiguous consent from the recipient. However, the consent must meet specific requirements:

Requirements for Valid Consent

1. Specific: The individual must consent specifically to receiving marketing messages, not just to general data collection. Generic consent to "receive communications" is insufficient.

2. Clear and unambiguous: The consent must be an active, affirmative act. Silence, inaction, or pre-ticked boxes do not constitute clear consent for DNC override purposes.

3. Documented: You must be able to prove that consent was obtained. Keep records of when, how, and what the individual consented to.

4. Current: Consent can be withdrawn at any time. If someone withdraws consent, you must stop marketing to them immediately.

Example of Valid Consent

A customer fills out a form that includes: "I agree to receive promotional SMS messages from [Company Name] about our products and services." The customer signs the form.

Example of Invalid Consent

A customer agrees to your Terms of Service, which include a clause buried on page 12 saying "you consent to receive marketing communications." This is not clear and unambiguous.

Exemptions

The DNC provisions include limited exemptions:

Business-to-Business Marketing

Messages sent to business telephone numbers (not personal numbers) for B2B marketing purposes may be exempt if the message is relevant to the recipient's role. However, this exemption is narrow and the PDPC interprets it strictly. If in doubt, check the registry.

Existing Business Relationship

If you have an ongoing relationship with the recipient (e.g., they are a current customer), you may have a basis for deemed consent. However, this does not automatically override a DNC registration. Best practice is to obtain explicit consent for marketing when onboarding customers.

Government and Public Interest

Messages from government agencies or for genuine public interest purposes are exempt.

Penalties for Non-Compliance

The PDPC takes DNC violations seriously and has actively enforced the rules. Penalties include:

Financial Penalties

• Organisations: Up to S$1 million per breach
• Individuals: Up to S$10,000 per message for unsolicited marketing

Published Enforcement Actions

The PDPC has published numerous enforcement decisions for DNC violations. Common scenarios include:

• Real estate agents sending mass SMS campaigns without checking the registry
• Insurance companies cold-calling registered numbers
• Retailers sending promotional SMS to customer databases without checking
• Marketing agencies sending messages on behalf of clients without performing DNC checks

For a detailed look at enforcement trends and penalty amounts, see our penalties guide.

Who Is Liable?

Both the organisation commissioning the marketing and any third-party marketing agency sending the messages can be liable. You cannot outsource your DNC obligations to a vendor — if they breach on your behalf, you are still responsible.

Best Practices for DNC Compliance

1. Build Consent into Your Customer Journey

When collecting contact details, include a clear consent mechanism for marketing:

• Use separate, unticked checkboxes for marketing consent
• Specify the channels (SMS, voice, fax) the customer is consenting to
• Keep consent records with timestamps

2. Check Before Every Campaign

Never assume a previous check is still valid. Numbers are added to and removed from the registry regularly. Always check within 30 days of sending.

3. Maintain an Internal Suppression List

In addition to DNC checks, maintain your own list of individuals who have:

• Withdrawn consent
• Requested to stop receiving marketing
• Complained about marketing messages

4. Include Opt-Out in Every Message

Every marketing SMS must include instructions for opting out. Example: "Reply STOP to unsubscribe."

5. Train Your Staff

Ensure everyone involved in marketing — from the marketing manager to the intern sending SMS — understands the DNC requirements. This is part of your broader PDPA compliance training obligations.

6. Audit Regularly

Review your marketing processes at least quarterly:

• Are DNC checks being performed consistently?
• Are records being maintained?
• Are opt-out requests being processed promptly?
• Are third-party marketing vendors compliant?

DNC Compliance as Part of Overall PDPA Compliance

The DNC Registry is just one component of the PDPA. Your overall compliance framework should address all 10 PDPA obligations, including appointing a DPO, maintaining a privacy policy, and having a data breach response plan.

Many businesses that fail on DNC compliance also have gaps in other PDPA areas. A comprehensive compliance assessment can identify all your gaps at once.

Check your full PDPA compliance status, including DNC readiness. ComplyHQ's AI-powered gap assessment evaluates your practices against every PDPA obligation and identifies what needs attention. Start a free assessment

Government Resources

• DNC Registry Portal — Register and perform DNC checks
• PDPC DNC Guidelines — Official guidance
• PDPC Enforcement Decisions — Published DNC enforcement cases

Related Articles

• PDPA Compliance Checklist for Singapore SMEs (2026 Edition) — Complete checklist including DNC compliance
• Understanding Consent Under PDPA — How consent works for marketing
• PDPA Penalties and Fines: What You Risk for Non-Compliance — Full penalty framework
• 10 PDPA Obligations Every Singapore Business Must Follow — All obligations explained