[luckylion]

What do people do then, do they just get lots of 20ies, or are they mostly paying electronically for anything > £20?

We have the a similar issue in Germany, but it's mostly with 200€ notes (and 100€ notes for a small shop, maybe). I've never had anyone even as much as look annoyed to being handed 50€.

[notahacker]

Mostly electronic payments for everything now, but you could fit a lot of twenties in a wallet (or write a cheque to pay a bill) when card payments weren't so widespread.