Introduction of Do Not Originate Protocol for Nuisance Calls

Posted on 17 Nov 2022

In December 2021 ComReg established the Nuisance Communications Industry Taskforce in order to confront the issues of nuisance communications and consumers being defrauded of money and personal information, such as PPS numbers and bank details. The NCIT includes ComReg and fixed and mobile telecoms operators, and meets monthly to discuss how best to tackle the problem of nuisance communications.

The NCIT has agreed a workplan to implement a range of interventions, which are designed to reduce the impact of nuisance communications on Irish consumers.

Do Not Originate List

As a first step, operators are moving to block phone numbers that are known to be fake. Calls pretending to be from trusted phone numbers will be stopped with the implementation of a “Do Not Originate” List. The DNO List comprises inbound-only phone numbers assigned to organisations as contact numbers for their callers, e.g. for consumer helplines and banking. As these numbers are never used to make outgoing calls, calls appearing to originate from the numbers are fake and the numbers have been spoofed. To implement the DNO List, operators will block calls appearing to originate from numbers on that list.

A DNO trial in September 2022 conducted by ComReg and the main telecoms operators was very effective - thousands of spoofed calls appearing to originate from phone numbers on the trial DNO List were blocked. Following that successful trial, ComReg and industry agreed to a wider roll-out of DNO, which is now underway

ComReg recently published a dedicated webpage at with further information and guidance.

For any queries on the Do Not Originate list please email