I bank with Nationwide who are supposed to be a building society. In my experience they're in every way just like a bank.

I bank at a credit union [1]. I specifically remember one year where they sent a letter saying roughly "We made too much money. Your account has been credited with your share of the excess." Of course, that's what a credit union implies but they're a bank to me so I'd be in the 7%.

[1] https://www.deltacommunitycu.com/