The three components
Interchange goes to the card issuer and is regulated for UK consumer cards. Scheme fees go to Visa or Mastercard. Acquirer margin is your provider's own charge — and it is the only part that is genuinely negotiable.
Providers who quote a single blended rate are bundling all three together, which makes comparison difficult by design.
Blended vs interchange-plus
Interchange-plus pricing shows each component separately, so you can see exactly what your provider earns. Blended pricing is simpler to read but almost always more expensive for businesses taking a high share of standard consumer debit cards.
- Ask for interchange-plus (IC+) pricing in writing
- Check the rate applied to commercial and non-UK cards separately
- Confirm authorisation fees per transaction — often 1-3p and easy to miss
Work out your effective rate
Divide total monthly card costs — including terminal rental, PCI fees, minimum monthly charges and authorisation fees — by total card turnover. That effective percentage is the only number worth comparing between providers.
Want this reviewed for your business?
Send us a recent bill and a consultant from our Cardiff office will tell you, honestly, whether you are paying more than you need to.