As previously reported on this blog, on 3rd July 2025, the Irish regulator ComReg launched its SMS Sender ID Registry to combat the growing threat of SMS fraud and smishing in Ireland. However, within the first two weeks of its rollout, the registry has encountered several issues affecting businesses, messaging providers, and the public. The Head of MEF Sender ID Registry Stefano Nicoletti explains more.

As of 11th July, the registry had recorded 14,011 registered SMS Sender IDs from 11,100 registered owners—a remarkable achievement. ComReg reports that these numbers continue to grow. In 2024 alone, 2.3 billion text messages were sent in Ireland, with an estimated 615 million being Application-to-Person (A2P) messages. ComReg platform will go live fully on October 3^rd, 2025.

Comreg identified operational issues causing the problem

Last week, Irish media reported issues with the mislabelling of SMS headers. Some legitimate messages were incorrectly flagged as “Likely Scam,” despite originating from trusted institutions such as banks, hospitals, and universities. This has caused confusion and the risk of missed appointments or financial alerts. While ComReg maintains that its platform is functioning correctly, they have recognised and identified operational issues.  These appear to stem from integration problems among technical partners and certain industry players.

First, businesses must register their Sender IDs with ComReg and authorise their respective Aggregator.  If they don’t’ do so, then their SMS header will flag as ‘Likely Scam’. This two-steps registration process may have caused glitches as some businesses seem to have completed the first step but then forgot to authorise (or did not know) their Sender ID with their Aggregators.

Non-participating Aggregators must register now

Secondly, if a provider is not a registered ‘Participating Aggregator’, then again, its SMS traffic will be re-labelled to ‘Likely Scam’. ComReg reiterated the importance of registering now to all aggregators on its website: 

“Organisations using SMS Sender IDs in their SMS text messages to mobile phone users in Ireland must register their SMS Sender IDs with ComReg now.”

As obvious as this request may be, it clearly has not reached all parts of the Irish messaging world, and some actors have yet to comply. We call upon all Aggregators operating in Ireland to comply to the new rules as soon as possible.

MEF’s Role 

Since launching its own voluntary SMS Sender ID Registry in July 2021, the Mobile Ecosystem Forum (MEF) has played a key role in supporting the Irish messaging ecosystem. Over the past four years, MEF has worked closely with the Banking & Payments Federation in Ireland (BPFI) , the National Cybersecurity centre (NCSC ROI), local MNOs, aggregators, government agencies, and financial institutions. We continue to assist customers and aggregators during the transition to ComReg’s mandatory registry. Our transition service runs until December 2025.

In recent weeks, MEF has been actively involved in escalating suspected smishing cases to mobile network operators and aggregators for traceback and investigation. As is often the case during transitions, fraudsters attempt to exploit early-stage vulnerabilities and confusion. We’ve observed this trend in Ireland and are working closely with merchants, aggregators and MNOs to combat emerging threats.

We remain fully supportive of ComReg’s mission to combat fraud and continue to monitor feedback from merchants and partners to help improve the new registry’s effectiveness

Head of MEF Sender ID Registry