Credit Card Surcharge Calculator
- You keep
- Processing fee
The cap stops you recovering the whole fee: you still pay $0.38 on this sale. Check your state's law before you start surcharging.
How the credit card surcharge calculation works
The credit card surcharge that covers your processing fee, the most the Visa and Mastercard rules let you add, and what the customer pays.
Enter the sale and your card rate
Use the percentage and per-transaction fee from your processor statement. 2.9% + $0.30 on a $100 sale is $3.20.
Gross up the surcharge
The fee is also charged on the surcharge, so covering it in full takes (2.9% × $100 + $0.30) ÷ (1 − 2.9%) = $3.30, not $3.20.
Apply the cap
Visa caps a surcharge at your merchant discount rate or 3%, whichever is lower; Mastercard at your rate or 4%. At a 2.9% rate the most you can add is $2.90.
See what is left
The customer pays $102.90, the fee on that is $3.28, and you keep $99.62. The $0.38 gap is the part of the fee the cap leaves with you.
Worked example. On a $100.00 credit card sale at 2.9% + $0.30, covering the whole fee would take a $3.30 surcharge. Visa's cap is the lower of your 2.9% rate or 3%, so you can add $2.90. The customer pays $102.90, the processor takes $3.28 and you keep $99.62, still $0.38 short of the full $100.
Credit Card Surcharge FAQ
How do I calculate a credit card surcharge?
Multiply the sale by your card rate and add the fixed fee, then divide by 1 minus the rate, because the processor also charges its fee on the surcharge. For $100 at 2.9% + $0.30: $3.20 ÷ 0.971 = $3.30. Then check it against the cap.
What is the maximum credit card surcharge?
Under Visa's rules, the lower of your merchant discount rate for that card or 3%. Under Mastercard's rules, the lower of your average effective merchant discount rate for Mastercard credit or its 4% Maximum Surcharge Cap. State law can set a lower limit or ban surcharges.
Can businesses charge a credit card fee?
In most US states, yes, on credit cards only and within the card network rules. Visa requires you to tell your acquirer at least 30 days before you start. Mastercard's rules ask for notice to Mastercard and your acquirer at least 30 days ahead. Some states prohibit or limit surcharging, so check your state's law before you start.
Can I add a surcharge to debit card payments?
No. Visa and Mastercard rules do not allow surcharges on debit or prepaid cards. Only credit cards can be surcharged.
How must I show a credit card surcharge to customers?
Visa requires a notice at the point of entry and at the point of sale, in store and online, and the surcharge must show as a separate line on every receipt. Mastercard requires clear disclosure at the point of interaction and the surcharge amount on the receipt.
Is a cash discount the same as a surcharge?
No. For a cash discount, Visa says prices must be shown as the card price per item, or card and cash prices side by side. The card total must not be reached by adding a fee for paying by card at checkout, or it may be treated as a surcharge.
Is it legal to charge a credit card fee in my state?
It depends on the state. Visa's own guidance says some states prohibit surcharging and others add requirements, and tells merchants to ask a lawyer. Check your state attorney general's or consumer protection office's guidance before you add a surcharge.
Sources: Visa: U.S. Merchant Surcharge Q and A, version 15 Feb 2024 (PDF, checked 20 Oct 2026) · Visa: Regulation and fees for merchants (surcharging notice) · Mastercard: Merchant surcharge rules (US)