eir owns Ireland's main fixed network, run by its wholesale arm open eir, and a mobile network also used by GoMo and Lyca Mobile. NJJ Boru, controlled by Xavier Niel and Iliad, holds more than 70% of eir. Its 3G network is being switched off in phases from 1 October to 6 November 2026.

Fixed network
- Network used
- Eir
- Technologies
- Fibre (FTTH)Fibre (FTTC)Copper
- Subscribers
- 899,000· June 2026, fibre broadband
- Coverage
- Ireland
Over 1.5M premises can connect to eir FTTH in June 2026. With FTTC, eir's fibre reaches 2.3M premises, 99% of Ireland.

Mobile network
- Network used
- Eir
- Technologies
- 5G4G3G2G
- Subscribers
- 1.615M· June 2026, eir and GoMo
- Coverage
- Ireland
eir's 5G reaches 99% of the population (August 2026). eir had 24.9% of mobile subscriptions excl. broadband and M2M in June 2026.