This may affect some of you as both customers and as purchasers, but as of 13th Jan, companies are no longer allowed to impose a surcharge for using particular cards. As I understand it an 'admin' fee across ALL methods of payment may be allowable but there now cannot be a charge for certain cards (eg credit cards). I know there are some suppliers who have previously had surcharges in place for credit card/paypal but not for debit cards, so it is worth checking with them when you next purchase.
Info here:
https://www.gov.uk/government/news/c...s-for-shoppers