If you cant get your passport, go to your home country on your expired ID and renew. You will have no problem going home on expired ID, then travel with your new one. No further problems.

Blah, Blah, Blah, Yes, BA has the right to do anything they want. Totally agree.

But any common sense has been totally lost by BA and all the defenders.

The OP has an EXPIRED ID Card. So, from one day to the next when the ID card expired, does your existence expire?
WHAT do you think changed?

Totally much ado about NOTHING and just one more reason of the thousands NOT TO EVER FLY B A

I don't see how it can - by the time a passenger boards the train, exit and entry immigration formalities have been performed ; if someone gets on the train then that person has cleared immigration

The premise of the OP's post is that he has a right of entry to the UK, but is being denied access to the UK border by BA. I don't believe Eurostar check your passport/ID at check-in, but if they did and had an issue, they could check it with the border officials at the same terminal, who would be the people determining entry in any event. If the OP doesn't have a right of entry (though given he can establish he is an EU citizen, by means of his expired ID, it is difficult to see on what basis), then better hanging out in Paris/Brussels/Budapest than in a UK immigration detention centre!

Good morning everyone! Glad my story keeps you entertained :)
Let me just make a few things very clear.

1. I never said I KNOWINGLY exited the UK with an invalid ID. I ALWAYS travel with my passport, I know exactly when my passport expires. Because the passport was not with me at the time, I decided to take my EU ID....I Forgot to check the expiration date. Probably because in my mind I had this idea that my passport is 5 years away from expiring. Who knows, anyway my fault for not checking the validity. I only discovered the ID was invalid upon arrival in Hungary.
2. Didn't express myself clearly. What I meant to say by "too much pain to renew", is that my embassy wont give me a temporary passport without a birth certificate
3. I agree that I'm the main one responsible for this but maintain that BA has some fault for letting me board in the first place. Since they didn't bother to check the validity when I left, why can't they return the same "favour" for my return to the UK? The annoying part is also that my wife mentioned that when she boarded the plane, the guys at the gate were looking at IDs super quickly and wasn't looking like they were checking validity, just for the name to match the ticket. Classic!

You need to stop blaming BA for your own actions and decisions. BA does not check documents for a passenger's benefit. If BA wanted to, they could stop all document checks and just accept all the fines imposed for carrying passengers with improper documents.

BA had no need to check at LHR whether you had documents to enter the UK because you were not travelling to the UK. Depending upon which country ID you had and when it was issued, you may have had sufficient documents to enter Hungary because your expired ID may be considered to have been automatically extended by 5 years. Hungary accepts such 'expired IDs,' while the UK does not. So, when you were travelling to Hungary your docs may have been OK and BA may have had no reason to deny boarding. You had to make sure that your documents were OK both to enter Hungary and then to come back to the UK. Putting the blame on BA that they did not check that you would be able to return is just misplaced.. Had BA denied you boarding at LHR on your way to BUD even though you had proper documents for Hungary, we'd be reading about how BA is at fault for not letting you travel (and in that case BA certainly would). If, however, you did not have proper documents to enter Hungary and the gate agent did not do their job properly, you can't just ask agents at BUD to also ignore their responsibilities and let you board the plane without proper documents.

So why have an expiry date at all? And if you have one but will make exceptions, how do expect an airport agent to make the distinction as to who to allow and who not to?
As an American Police man said to me "Sir, when you have rules, you do not have to rely on common sense"

Some years ago a friend (EU national like the OP) had his passport stolen in the US the day he was meant to come back. He went to the airport in the US, announced he no passport had since passport and the airline contacted the UK Home office which within 30mins or authorised his entry and provided a reference number to show at immigration. I'd tend to think that BA did contact the Home Office; I understand this is a standard procedure in these cases. What I don't understand is why the Home Office would deny entry to a permanent resident.

If the OP confirms their nationality, it may be easier to work out if there was an error or not made on the outbound flight
eg timatic shows for a German passport holder resident in the UK destination Hungary
"Nationals of Germany are allowed to enter with an expired passport or expired national ID card. These documents are accepted when expired for a maximum of 1 year."
whereas if you do the journey in reverse - "Passports and other documents accepted for entry issued to nationals of Germany must be valid on arrival."

Looks like the OP is a busy chappy on Tripadvisor too ;)

https://www.tripadvisor.com/ShowTopi...ir_Travel.html

https://www.tripadvisor.com/ShowTopi....html#96427071