Bulk SMS in Singapore: PDPA, DNC and Sender ID Rules Explained

SMS remains an important channel in Singapore for one-time passwords, appointment reminders, delivery updates and marketing promotions. At the same time, SMS scams have been a serious concern, and Singapore has responded with some of the clearest rules in the region: a mandatory sender ID registry, the Do Not Call Registry and the Personal Data Protection Act.

This guide explains what those rules mean for businesses and how to run effective SMS campaigns in Singapore.

This article is general information, not legal advice. Check the latest guidance from the PDPC and IMDA, or consult a Singapore lawyer.

The Singapore SMS Sender ID Registry (SSIR)

The SSIR, overseen by the Infocomm Media Development Authority (IMDA) and operated by the Singapore Network Information Centre (SGNIC), lets organisations register the alphanumeric sender IDs they use, such as "DBS" or "SHOPEE". Since 31 January 2023, registration has been mandatory for organisations that use alphanumeric sender IDs to send SMS to Singapore mobile numbers.

Key points:

• Organisations register their sender IDs through SGNIC, and the aggregators that send SMS on their behalf must be registered and participating
• Messages using unregistered alphanumeric sender IDs are labelled "Likely-SCAM" before they reach recipients
• Registration helps protect your brand from impersonation by scammers
• Organisations generally need a Singapore Unique Entity Number (UEN) to register

If you plan to use a branded sender ID, register it before launching campaigns, and confirm that your SMS provider routes through a participating aggregator.

The Do Not Call (DNC) Registry

Under the PDPA, the DNC Registry, administered by the Personal Data Protection Commission (PDPC), lets individuals register their Singapore telephone numbers to opt out of receiving marketing messages and calls. There are separate registers for voice calls, text messages and fax.

In general, before sending a specified message, which is a marketing message offering or promoting goods, services or business opportunities, to a Singapore number, you must:

• Check the number against the relevant DNC register within the validity period of the results, unless you have the individual's clear and unambiguous consent in written or other accessible form
• Include your organisation's identification and contact information in the message
• Avoid concealing the calling line identity for voice calls

Messages that are purely transactional, such as order confirmations or appointment reminders without promotional content, are generally not specified messages, but mixing marketing content in changes that.

The PDPA also prohibits sending specified messages to numbers generated or obtained through dictionary attacks or address-harvesting software.

PDPA data protection obligations

Beyond the DNC provisions, the PDPA's data protection obligations apply to the personal data you collect, including phone numbers:

• Consent: collect, use and disclose personal data with consent, or under an applicable exception
• Purpose: tell people why you are collecting their data
• Protection: take reasonable security measures
• Retention: do not keep data longer than needed
• Access and correction: respond to requests
• Data breach notification: notify the PDPC and affected individuals of notifiable breaches

The Spam Control Act

The Spam Control Act regulates unsolicited commercial electronic messages sent in bulk, including SMS. For unsolicited bulk messages, it requires labelling, such as "" at the start, an unsubscribe facility and accurate sender information. Most legitimate businesses avoid this by sending only to people who have consented.

Best practices for Singapore SMS campaigns

1. Register your sender ID with the SSIR and use a participating aggregator.
2. Collect clear consent through an unticked box, keyword sign-up or written form, and record it.
3. Check the DNC Registry for marketing messages unless you hold clear and unambiguous consent.
4. Identify your business in every marketing message, with contact information.
5. Offer an easy opt-out and process it promptly.
6. Keep messages short and clear. Avoid generic link shorteners that resemble scams.
7. Respect timing. Send during reasonable hours.

Scam-safe messaging

Singapore residents are increasingly cautious about links in SMS. Banks and government agencies have moved away from clickable links in many messages. To build trust:

• Use your registered sender ID consistently
• Avoid asking for passwords, OTPs or payment details by SMS
• Prefer your own branded domain for links, or direct customers to your app
• Tell customers how you will and will not contact them

Common use cases

• OTPs and login verification
• Appointment reminders for clinics, salons and service centres
• Delivery and collection notices
• Payment reminders
• Opted-in marketing promotions for retail, F&B and e-commerce
• Event reminders

Writing effective texts

"ORCHARDSPA: Your facial is confirmed for Sat 14 Jun, 3pm. Reply 1 to confirm or call 6123 4567 to reschedule."

"BAKEHAUS: 20% off all cakes this weekend for members. Show this SMS in store. Reply STOP to opt out. 6123 4567"

Keep it under 160 characters to avoid multi-part charges, and remember that non-Latin characters, such as Chinese, use Unicode encoding with fewer characters per segment.

SMS vs WhatsApp in Singapore

WhatsApp is very widely used in Singapore and suits rich, two-way conversations, while SMS remains essential for OTPs, critical alerts and reaching every phone. The DNC provisions can also apply to marketing messages sent through other messaging channels to Singapore numbers, so the same discipline applies.

Pricing

Prices are in US dollars and follow our current price list. SSIR registration fees charged by SGNIC and DNC checking fees charged by the PDPC are separate. Our prices are positioned below typical Singapore provider rates. Contact us for an exact quote.

Common mistakes

• Using an unregistered alphanumeric sender ID
• Skipping DNC checks for marketing messages without clear and unambiguous consent
• Relying on outdated DNC check results
• Omitting business identification
• Buying phone number lists
• Mixing promotions into transactional messages

Industry examples

• F&B: member offers, new menu launches and reservation reminders
• Retail and e-commerce: flash sales for opted-in members, delivery notices and click-and-collect alerts
• Healthcare: appointment and vaccination reminders without sensitive details
• Education and enrichment centres: class reminders and schedule changes
• Property: viewing confirmations for people who registered interest
• Logistics: delivery windows and collection notices

Integrating SMS with your systems

Connect SMS to your booking system, POS, e-commerce platform or CRM using an API, so reminders and updates send automatically and opt-outs and consent records stay in one place. Test messages on major Singapore networks before launching large campaigns, and monitor delivery reports for failures.

Data security for SMS lists

Phone numbers and messaging histories are personal data under the PDPA. Restrict access to contact lists, use strong passwords and two-factor authentication on your SMS platform, and agree data protection terms with your provider. Delete numbers you no longer need.

Measuring results

Track delivery rates, click-throughs, redemptions of SMS-only offers, opt-outs and, for reminders, the reduction in no-shows. Compare campaign results by segment and time of day to refine future sends.

Choosing an SMS provider in Singapore

Confirm that the provider routes through an SSIR-participating aggregator, supports your registered sender ID and offers clear per-message pricing.

How DND Teams helps

We provide bulk SMS in Singapore through registered routes, with support for SSIR onboarding, consent capture and DNC processes. Read our Singapore SMS compliance overview, then request a free review.

Prices shown are indicative "starting from" figures in US dollars and exclude taxes and third-party charges (such as Meta or carrier fees) unless stated. Contact us for an exact quote. This article is general information, not legal advice, and reflects our understanding as of October 2026.