Is that really true, though? Rabo had 90,000 customers. I know they weren't a full service bank but within their narrow focus they obviously did enough things well enough to attract a large base. I'd certainly take a close look at any new contenders. Even a half decent credit rating and I would be with them like a shot. I'm finding the lack of choice is reaching scary proportions, and I don't mean that as hyperbole whatsoever.
Yes, I think it is true.
Often, there is overlap, where a customer could have an account with more than one bank. Each bank conveniently claims the customer to help bump their own numbers, but ultimately it's the bank where most of the transactions take place that should count as the principal retail bank.
Consider RaboDirect, ACC (who were a separate retail bank, even though Rabo owned), Danske, PostBank, Hallifax.... All were challenger banks, many offered more competitively priced services than AIB or BoI, but none of them remain. I know the banking crisis played it's part, but if they had significant retail businesses here, at least some would remain open (even if they'd merged or been sold on to another stronger bank etc.).
As things stand, I think AIB & BoI continue to have something like 70% - 80% of the retail banking market. That's far from a competitive market. KBC, PTSB and UB share the remainder. While it might be interesting to ask all of the banks to tell us their customer numbers and add them all up, I suspect that we'd end up with a number equal to about 2-3 times our population.
Ultimately, it comes down to one thing - as a nation, we love to bitch and moan in the pubs etc., but we are very slow to vote with our feet. If we took more definitive action, BoI might be treating their retail customers a little better, Ulster Bank might have invested sufficiently to fix it's IT problems etc. as if they didn't, they'd have lost most of their customers by now.