Short answer
The SMS Sender ID Registry (SSIR) is Singapore's register of alphanumeric sender IDs, run by SGNIC under power delegated by IMDA. Organisations sending SMS to Singapore mobiles must register their IDs, and unregistered IDs are marked Likely-SCAM. You need a Singapore UEN, and messages must go through Participating Aggregators. Registration typically takes about 19 calendar days with complete documents.
What does SSIR require?
- Eligibility: a valid Singapore unique entity number (UEN); foreign businesses can qualify through a local subsidiary or branch with a UEN.
- Format: up to 11 characters including spaces, underscores and hyphens; no Chinese or Cyrillic characters; not generic.
- Aggregators: only Participating Aggregators licensed by IMDA can handle registered IDs.
- Fees: set in the SSIR User Agreement and non-refundable.
How does registration work?
- Choose short, brand-specific IDs, one per transactional and promotional use if you want to separate them.
- Prepare UEN details and an authorisation letter naming the IDs and your aggregator.
- Submit each ID in the SSIR and pay the fee.
- Select the Participating Aggregators that will send for you.
- Test an OTP and a promotion on Singtel, StarHub and M1 handsets.
What happens if you do not register?
Unregistered sender IDs are marked Likely-SCAM, which IMDA describes as working like a spam filter. Earlier IMDA material said unregistered messages could eventually be blocked, but we found no official source confirming a date. Marketing texts also fall under the PDPA Do Not Call rules. OmniChannels.ai prepares and files the registration with you; approval stays with SGNIC and IMDA.