AI Voice in Singapore 2026: IMDA, Numbering Plan Issue 2, and Anti-Scam Filters

Singapore runs one of the most disciplined telecom regimes in Asia. IMDA's National Numbering Plan Issue 2 dropped in February 2026, the SSIR Likely-SCAM labelling has cut SMS scams by 70%, postpaid SIMs are capped at 10 per person from 28 February 2026, and PDPA on voice biometrics is strictly enforced. AI voice agents must operate inside a tight box.

How telephony works there

IMDA (Infocomm Media Development Authority) administers numbering under the Telecommunications Act and the National Numbering Plan. Singapore uses 8-digit numbers with prefix 6 (fixed-line), 8/9 (mobile), 1800 (toll-free), and 3 (level-3 IP/VoIP). The National Numbering Plan Issue 2, published February 2026, refreshes the framework with updates on M2M ranges, 800 numbers, and short codes.

Twilio offers Singapore DIDs in the 6, 3, and 8 ranges plus 1800 toll-free. The Singapore media edge gives sub-10 ms RTT to local users — among the lowest globally. PSTN-IP migration is complete; SingTel, StarHub, M1, and Simba interconnect via SIP. CLI rules require allocated, callable numbers; spoofed CLIs are blocked at the originating carrier under the Anti-Scam Filter.

Regulatory landscape

Three regimes apply. First, IMDA numbering and SSIR (SMS Sender ID Registry): any alphanumeric Sender ID for SMS must be registered; non-registered SMS is labelled "Likely-SCAM" since 31 January 2023, with cases dropping 70% over the following three months. Postpaid SIMs are capped at 10 per person from 28 February 2026; over 1.1 million subscribers have activated international-call blocking. Second, the Do Not Call (DNC) Registry under the PDPA: marketing calls and SMS must scrub against the DNC daily; specific opt-outs are honoured immediately. Third, the PDPA itself: consent, purpose, notification, and access; voice and voice-biometrics are personal data with stricter consent for biometrics.

For AI voice specifically, IMDA's 2024-2025 advisory and the Cyber Security Agency's 2026 Anti-Scam Guide expect AI disclosure at the start of any commercial interaction. The Personal Data Protection Commission (PDPC) treats undisclosed AI voice as a deceptive practice and a PDPA Section 13 (notification) violation. Maximum financial penalties under PDPA are SGD 1 million or 10% of annual turnover (whichever is higher).

CallSphere implementation

CallSphere runs Twilio across all six verticals (Healthcare AI, Real Estate AI, Sales Calling AI, Salon AI, IT Helpdesk AI, After-Hours AI), with 37 agents, 90+ tools, 115+ DB tables, HIPAA + SOC 2, and pricing at $149 / $499 / $1499 with a 14-day trial and a 22% lifetime affiliate. Singapore tenants get Twilio SG DIDs in the 6 (fixed) or 3 (IP) range, plus 1800 toll-free for inbound (Salon, After-Hours, Healthcare). SMS Sender ID is registered with SSIR under the tenant's UEN; the Likely-SCAM label is mathematically impossible because we always send from a registered ID. The AI agent opens with "this is an automated call from [brand], you are speaking to an AI" — PDPA Section 13 transparency. DNC scrub runs daily, with category-level honour. PDPA consent is captured with timestamp, IP, purpose, base, and stored for at least 3 years; recordings encrypted with retention bounds.

Build and launch steps

flowchart LR
  A[Twilio SG subaccount + Singapore edge] --> B[Provision 6/3 DID + 1800]
  B --> C[Register SMS Sender ID in SSIR]
  C --> D[DNC daily scrub]
  D --> E[AI + identity disclosure first sentence]
  E --> F[PDPA consent log + recording retention]

1. Create a Twilio SG subaccount; pin media to Singapore (sub-10 ms RTT).
2. Provision a 6 fixed-line or 3 IP DID and a 1800 toll-free for inbound.
3. Register your SMS Sender ID with SSIR under your UEN to avoid Likely-SCAM labels.
4. Subscribe to the DNC Registry; scrub daily by category.
5. Capture PDPA consent: timestamp, IP, purpose, base; store ≥ 3 years.
6. Configure the AI agent to disclose AI + identity in the first sentence; encrypt recordings, document retention.

FAQ

What is SSIR? SMS Sender ID Registry. From 31 January 2023, non-registered alphanumeric Sender IDs are labelled "Likely-SCAM" by the network. Registration is mandatory if you want a clean send.

Is AI voice marketing legal in Singapore? Yes, with PDPA consent, DNC scrub, AI disclosure at call start, and identity transparency.

What changed in February 2026? IMDA published the National Numbering Plan Issue 2, and the postpaid-SIM cap of 10 per person took effect on 28 February 2026.

Can I send marketing SMS from a 10-digit number? Yes, if the number is registered to the sending entity and the campaign respects DNC. Alphanumeric Sender IDs require SSIR registration.

Sources

• IMDA: National Numbering Plan Issue 2 (Feb 2026)
• IMDA: Anti-Scam Measures
• PDPC: Personal Data Protection Act
• Toku: Labelled "Likely Scam" under SSIR

Start a 14-day trial on a Singapore number, see pricing at $149/$499/$1499, or contact us for IMDA / Twilio SG setup help.

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