Contact Us

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SEMO Helpdesk

Republic of Ireland: 1800 726 772
Northern Ireland: 0800 072 6772
International: +353 1 237 0584

The SEMO Helpdesk is available Mon-Fri from 9.00am until 5.00pm. We operate a voicemail service if we are unavailable.

SEMO LCF Hotline

Phone Number: +44 (0) 28 90 707415

This should only be used for emergency operational issues relating to Limited Communication Failures (LCF). The process for declaring and submitting a LCF can be found on the SEMO website.

The Hotline is available 24/7 on an interim basis.

The latest LCF procedure and supporting LCF tool are available to download.

Our Locations

Republic of Ireland

SEMO Customer Service
160 Shelbourne Road
Dublin 4
D04 FW28

Fax: +353 1 526 6416

Northern Ireland

SEMO Customer Service
Castlereagh House
12 Manse Road
Belfast BT6 9RT

Fax: +44 2890 707555

Complaints Procedure

If you are unhappy with the quality of service you have received, you have the right to complain. Please direct these complaints to for the attention of the Front Office Manager. An escalation process will be initiated and your complaint will be addressed.

As per the Trading & Settlement Code participants may raise a dispute in respect of a Settlement query – please see Agreed Procedure 14 – Disputes.

For further information, view SEMO's full Customer Charter.