Originally Posted by
AirbusA350
So essentially, with Ireland being within the Common Travel Area, one does not need to pass through UK immigration upon landing in the UK, but still do need to pass through UK customs. I suspect the gate you arrived at did not have the appropriate routes/access to lead you past immigration (but not before customs). Slightly digressing but I've always found it curious as to why at DUB, UK arrivals are subject to Irish passport control but not in reverse! If anyone else here knows the reason, I'd be curious to know
Avios is no longer being given as compensation from multiple reports here.
I would hazard a guess it's due to the UK being better setup to handle domestic arrivals. I could be wrong!
You also technically don't need a passport to pass through Irish immigration. It's only the fact that most airlines mandate that a passport is carried as an acceptable form of ID that means the majority of passengers present one.
I arrived into Dublin by sea last year and there were no checks whatsoever.