Merchant Processor Interchange-Plus Fee Calculator

Interchange, markup, and per-item fees on real transaction volume

At a $68 average ticket and 420 monthly transactions ($28,560 total volume), an interchange-plus pricing structure of 1.8% + $0.10 interchange plus a 0.25% + $0.05 processor markup costs $648.48/month -- an effective rate of 2.27%, or $1.544 per transaction.

Interchange-plus pricing separates the two components deliberately: interchange (1.8% + $0.10 here) is set by the card networks and passed through at cost, while the markup (0.25% + $0.05) is the processor's actual margin -- the only piece that's negotiable.

At this ticket size, the per-item component matters more than it would on a larger average ticket: $0.15 in combined per-item fees ($0.10 + $0.05) is about 0.22% of a $68 ticket, but the same $0.15 would be a much smaller share of a $200 ticket -- per-item fees hit small-ticket, high-volume businesses hardest.

Why the effective rate (2.27%) differs from the headline rate

Illustrative interchange-plus. Card-brand assessments change by MCC. Effective rate blends the percentage and per-item components across your actual average ticket, which is why it doesn't match either the 1.8% interchange or the 0.25% markup on their own -- it's closer to their sum once the fixed per-item fees are annualized against ticket size.

Interchange rates themselves vary by card type (rewards cards typically carry higher interchange than basic debit), transaction method (card-present vs. card-not-present), and merchant category code (MCC) -- the 1.8% used here is an illustrative blended rate, not a universal fixed figure.

Ticket and count must both be greater than zero for the monthly cost to compute, since the per-item fees scale directly with transaction count.

Comparing this to other payment structures

For a flat-rate processor instead of interchange-plus, the Stripe Fee Calculator and PayPal Fee Calculator use simpler percentage-plus-fixed pricing that's easier to compare but often costs more at volume.

If invoicing rather than card-present sales is the main channel, the Square Invoice Fee Calculator prices that specific flow.

Frequently Asked Questions (FAQ)