|Key people||Steve Fitzpatrick, General Secretary|
|Office location||Dublin, Ireland|
The union was founded in 1922 as the Irish Post Office Engineering Union, splitting from the British Post Office Engineering Union following the establishment of the Irish Free State. The following year, it merged with the Irish Postal Union and the Irish Postal Workers' Union, forming the United Postal Union, but the IPOEU was unhappy with the arrangements, and so withdrew before the merger was completed, continuing an independent existence.
- 1950s: Malachy Dooney
- 1967: Seamus De Paor
- 1990: David Begg
- 1997: Con Scanlon
- 2004: Steve Fitzpatrick