Flying in and out of Dublin Oct.2025. Rental car touring around Ireland & Northern Ireland.. Will be crossing borders. Not going through border security in Belfast? Basically Dublin to Belfast to Dublin (sights along the way). Is ETA needed?
Technically, Yes, you are crossing the border. Will anyone ever check or know? Probably not. Get pulled over by the police for a minor infraction, probably, maybe a rare border check. For the cost and the ease of getting it? Best just to get it.
It is good for two years. I'd get it and then I would justify an entire extra trip to the UK in that time period to "make sure I get my money's worth." Nobody is better at finding reasons for more travel than me!
Is ETA needed?
Yes.
Northern Ireland is part of the UK.
US passport holders are required to have an ETA to legally enter the UK.
Therefore to be compliant with UK law you need an ETA
Above assumes you are a US passport holder.
immigration act `1971 says this
Immigration rules may require an individual of a description specified in the rules not to travel to the United Kingdom from any place (including a place in the common travel area), whether with a view to entering the United Kingdom or to passing through it without entering, unless the individual has an ETA that is valid for the individual’s journey to the United Kingdom
A ETA IS REQUIRED
https://www.legislation.gov.uk/ukpga/1971/77/part/1A
Why even debate this? It’s required, cheap, and easy to get. In addition to be a good tourist by complying with the law, it’s cheap insurance against being caught without.
Thank you everyone for all your recommendations. We had conflicting information on ETA requirements.
Not wanting to be cheap (as inferred) just want to be a knowledgeable, respectful observer of all laws/customs when traveling.
As always RS travel forum is a great travel tool.