Ireland Eircode validator
How the Eircode format works
- Format
- Routing key (letter + digit + digit-or-W) followed by a 4-character unique identifier
- Example
- D02AF30
Things to watch for
- Format-only check — does not confirm the Eircode actually exists
- First 3 characters are the routing key (area), the last 4 are the unique address identifier; normally written with a space between them
^[A-Z][0-9][0-9W][0-9A-Z]{4}$An Irish Eircode is the 7-character code Eircode Ltd introduced in 2015 to identify Irish addresses, and it works differently from most postcodes worldwide. Rather than grouping many addresses under one shared code, the first 3 characters (a routing key, e.g. D02) name a broad area, while the last 4 characters are a unique identifier belonging to exactly one address — no two homes share a full Eircode. That approach was built to solve a real gap: many Irish addresses, particularly in rural areas, had no house number or named street for a conventional postcode grid to attach to.
Because the identifier half mixes letters and digits with few constraints, a dropped or swapped character routes to a different specific address rather than merely a different neighbourhood — the cost of a wrong Eircode is more precise, and less forgiving, than a wrong area-based postcode elsewhere.
How this validator works
This tool checks that the input is a letter, then two letter-or-digit characters (the routing key), followed by four more letter-or-digit characters (the unique identifier) — accepted with or without the customary space between the two halves — entirely in your browser, with nothing sent to a server.
What a pass doesn’t tell you
An Eircode’s identifier half has no simple check-digit rule this tool applies, so matching the routing-key-plus-identifier shape is the most a client-side tool can confirm — not that Eircode has actually assigned that code to a real address. Confirming that requires Eircode’s own address finder.
Scope: this page and tool cover format validation only — not address lookup or confirming a specific Eircode is currently assigned.
Eircode FAQ
How is an Eircode different from a typical postcode?
Most countries' postcodes cover an area shared by many addresses. Eircode, introduced in 2015, is unique per individual address instead — no two homes anywhere in Ireland share the same full 7-character code. That design exists because a large share of Irish addresses, especially rural ones, historically had no house number or street name a conventional postcode grid could hang off.
What's the difference between the routing key and the unique identifier?
The first 3 characters (a letter followed by two letters or digits, e.g. D02) are the routing key, naming a broad delivery area much like a traditional postcode district. The last 4 characters are a unique identifier assigned to one specific address alone, conventionally written after a space, e.g. D02 AF30.
Does a correctly formatted Eircode mean it actually exists?
No. This tool only confirms the string matches the routing-key-plus-identifier shape — it doesn't check it against Eircode's actual address database. Confirming an Eircode is real, and seeing exactly which address it names, requires Eircode's own finder tool.