I have booked a flight from Bangkok to Dublin, Ireland with my girlfriend in late April. We have done this trip twice before via Abu Dhabi The last 2 times we went, she had to get a UK visitors visa and a multi-entry Irish visa as she would be leaving Ireland to go north and then coming back again for the return flight. British airways told us that we need to get a transit visa for my girlfriend as we will land in London first and then connect to Dublin. So if she already has a UK visa, should she also need a transit visa to go from London to Dublin?

Can't see why you would need a transit visa. The UK visitor visa is multi-entry,

The answer is you might or might not need a transit visa!! If BA say you do, then you do!

The Irish Republic is part of the Common Travel Area and as such there is no requirement for a passport. Many airlines require you to use one anyway! On arrival at Heathrow passengers go through Immigration and therefore are subject to immigration control.

If you check the .org website 'Do I need a visa?' it states that a transit visa is required. However it then states that you may not require one if certain requirements are met. You must have a valid visa for the Irish Republic, arrive by air and have ongoing flights the same day.

As I said, you might or might not, clear as mud!

The reality is that if BA require it then it will be needed to prevent boarding being refused in Thailand.

https://www.gov.uk/check-uk-visa

Sorry misread the original post! If there is a valid UK visa there should not be a problem unless BA think there will be one. Still comes back to what BA say. An immigration officer might just decide the visa holders circumstances have changed!!

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