18 Sep 2017 9:59 PM:
There is no such thing as an Irish NIE or UK NIE. From my understanding, your NIE ( Numero Identifacacion Extranjero) remains the same forevermore and is unique to you as an individual irrespective of your nationality. Brexit should have no bearing on your current NIE number.
Whilst Brexit continues to be uncertain in regards how it is going to affect UK Ex- Pats living or travelling within Spain, your current NIE Number will not be an issue for you.
However, you should consider how you yourself classify your own nationality i.e. UK citizen or Irish citizen as this is what will have a bearing on the issue of Brexit and EU rulings. Travel and living in Spain etc.
Thread:
HOW TO CHANGE ENGLISH NIE TO IRISH NIE?
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