Postal codes in the Republic of Ireland

In Ireland, rural addresses are specified by the county, nearest post town, and the townland. Urban addresses are specified by county, city or town name, street name, house number or name, and apartment or flat number where relevant. 35% (over 600,000) Irish premises have non-unique addresses due to an absence of house numbers or names. In smaller towns and many townlands, this requires postal workers to remember which family names correspond to which house.

For this reason, a postal code system called Eircode was launched in April 2014. Eircode suffixes an identifier that is unique to each premises. The system was criticised at its launch for its estimated ten-year cost of €27 million, omissions and inaccuracy, in addition to not being immediately available with satnav systems or Google Maps.

However, since September 2016 the system is available on Google maps.

Responsibility for the current postal delivery system rests with An Post, a semi-state body; however, the Department of Communications, Energy and Natural Resources (DCENR) retains the right to regulate addresses if they wish so.

In Dublin city and its suburbs, a system of postal districts was introduced in 1917 by the Royal Mail with the prefix "D", and retained after Ireland became an independent country, without the prefix. However the use of district numbers by the public did not begin until 1961, when street signs displayed postal district numbers. Prior to that time, street signs only displayed the street name in Irish and English.

The Dublin system had 22 districts - Dublin 1, 2, 3, 4, 5, 6, 6W, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 20, 22, 24. These were incorporated into the new routing keys now being used with the Eircode national postcode system as D01, D02, D12, D22, etc.

In Cork, there are also numbered districts, e.g.: the 'PATRICK STREET' (Sráid Phádraig) sign will display the digit '1', but these are not encountered in postal addresses. Cork has four postal districts. District 1 covers the city centre and large parts of the surrounding city. District 2, administered from the Ballinlough sorting office, covers the south-east, District 3 (from Gurranabraher) covers the north-west while District 4 (from Togher sorting office) covers the south-west. In practice, these numbers are used only internally by An Post and rarely used on mail. The numbers are not used in the new Eircode system.

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