POS Processing Fee Calculator: Flat-Rate vs Interchange-Plus
Compare Square published flat rates against an interchange-plus quote, including hardware amortisation. Every formula and assumption is listed under the calculator. Change any default that does not match your venue.
Interactive calculator
Flat-rate (Square) vs interchange-plus contract: monthly cost
Interchange-plus quote (your numbers)
Transactions / month
1,579
Square effective rate
3.21%
processing only
Square all-in / month
US$1,978
Contract all-in / month
US$1,651
effective 2.46% processing
Contract saves per year
US$3,926
Formula & assumptions
Square fees use published rates: US (Square Free) in-person 2.6% + 15¢, online 3.3% + 30¢; AU in-person 1.6%, online 2.2% (sellers signed up from 30 May 2024). Source: squareup.com/us/en/payments/our-fees and squareup.com/au/en/pricing.
Transactions = volume ÷ average ticket. Interchange-plus = volume × (blended interchange % + processor markup %) + transactions × per-transaction fee.
Assumptions you control: blended interchange (default 1.9% US is a rough mixed debit/credit card-present estimate; AU interchange is far lower, try 0.5–0.8%), markup, software subscription and hardware costs. Toast and Lightspeed do not publish one fixed rate, so enter the numbers from your own quote. Hardware is straight-line amortised over the months you set. Early-termination fees, chargebacks, PCI fees and tax are not included.
General information only. Not payroll, legal or financial advice. Check figures with your accountant or payroll provider.