I was recently Poundless at LHR after arrival from the Continent. Looked for an ATM and picked out one by an Amex office (apparently Amex related). But, I think I got sorta ripped off because there was a, IIRC, a 5.5% surcharge added on.

Had I known that I could pay for my Tube ticket in London with a credit card I would have just annulled the transaction and gone into town--but, it had been a very long time since I was in the UK and just didn't know.

So, are some or all of the ATMs at LHR charging excess "commissions?"

I believe I did better in London itself, especially when out of the totally tourist areas--but, what do FTers who know something about London ATM (especially at LHR) use for converting dollars to pounds say?