As part of anti-scam measures, Telcos to introduce option for mobile subscribers to block calls from international numbers

1. As part of multi-layered measures to protect the public from scams, IMDA has worked with the Telcos (Singtel, M1, Starhub and SIMBA) to allow subscribers to opt in to block incoming calls from international numbers on their mobile phones.

Option to block calls from international numbers

2. In Singapore, approximately 1.6 billion international calls are received annually. These include calls made by scammers, many of whom operate from overseas. To combat the threat posed by international scam calls, IMDA and the Telcos have progressively introduced measures. This includes upfront blocking of all international calls that exhibit unusually high frequency, as these are likely scam calls made using automated systems. In addition, all international incoming calls where the caller ID is falsified with a +65 prefix to resemble a call made from Singapore, were also identified and blocked.

3. From January to September 2023, more than 300 million scam calls were blocked by our Telcos. This translates to approximately one in every four incoming calls from international numbers blocked for this period. All remaining calls from international numbers are tagged with the “+” prefix to remind the public to be vigilant when answering such calls. To further protect users who do not wish to receive calls from international numbers, Telcos are now introducing the option for subscribers to block such incoming calls on their mobile phones. This service is available from 5 January 2024 onwards.

4. By opting in, all incoming calls made from international numbers will be blocked. Calls made from Singapore numbers (e.g. Singapore users roaming overseas and calling home), will still be received as per normal. Subscribers can enable and disable the international number blocking option based on their needs. For example, a subscriber can opt in to enable the international number blocking as a default, but disable the service when travelling overseas and expecting calls from international numbers (e.g. from the hotel or on-ground transport).

5. Enabling or disabling the international number blocking option can be made through various channels provided by the Telcos, including call, SMS and/or through the Telcos’ app. Mobile subscribers should approach their respective Telcos to understand the service scope and how to sign-up (please refer to Annex A (169.31KB) for further information on signing up from the Telcos).

IMDA continues to partner the public in the fight against scams

6. Beyond the option to block incoming calls from international numbers, IMDA is continuing to work with Telcos to extend this option to block SMS from international numbers. By mid-2024, subscribers will have the option to block both calls and SMS from international numbers on their mobile phones.

7. These new measures are part of an ongoing multi-layered approach to strengthen protection against scams. IMDA has been working with the Telcos to systemically reduce scam calls and SMS coming through the communication networks.

8. Combatting scams is a whole of society effort, and the public should continue to remain vigilant. The public should continue to exercise caution when receiving calls and SMS as scammers’ tactics continue to evolve. Scammers will continue to change their methods and tactics and there is no fool-proof measure even as we continue to monitor and implement additional safeguards. IMDA will continue to work with other stakeholders in the fight against scams. A discerning public is the key in this fight, where consumers are individually alert and raise collective awareness by sharing scam prevention tips with friends and loved ones.

Please refer to Annex B (346.36KB) for more information on IMDA’s anti-scam measures.