To find what you keep from an invoice, subtract the processor’s fee from the amount charged. For a percentage-plus-fixed fee, the calculation is payout = gross charge − (gross charge × rate + fixed fee). To charge enough to receive a target payout, use gross charge = (target payout + fixed fee) ÷ (1 − rate). These figures describe the payout after processing only—not business profit or after-tax income.
Calculate the fee and payout from an invoice
Use three values:
- Gross charge (G): the amount charged to the client.
- Percentage rate (r): the processor’s percentage expressed as a decimal. For example, 2.9% is 0.029.
- Fixed fee (f): the per-transaction amount in the currency received.
For a simple percentage-plus-fixed fee, calculate:
- Processing fee = G × r + f
- Payout after processing = G − (G × r + f)
For example, if the rate is 2.9% plus $0.30 and the charge is $100, the fee is ($100 × 0.029) + $0.30 = $3.20. The payout is $100 − $3.20 = $96.80, before any other costs.
Set a charge that yields a target payout
To calculate the gross charge needed for a target payout, rearrange the payout equation:
Gross charge = (target payout + fixed fee) ÷ (1 − percentage rate)
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Suppose you want a $100 payout under a 2.9% + $0.30 fee. The calculation is ($100 + $0.30) ÷ (1 − 0.029), or approximately $103.40 before final currency rounding.
- Enter the target payout and the exact rate and fixed fee that apply to the transaction.
- Calculate the gross charge with the formula above.
- Round the charge to the currency’s precision, then recalculate the fee and payout using that rounded charge. Adjust by the smallest currency unit if needed to reach the target.
This gross-up works when the same percentage-plus-fixed fee applies to the whole charge. If the transaction also incurs an international, currency-conversion, platform, refund, or other fee, calculate that separately using the applicable terms.
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Why the fee rate depends on the transaction
A rate from one provider or payment type is not a universal freelance rate. Check the schedule for your provider, account market, received currency, plan, payment channel, and transaction type. Compare the percentage, fixed fee, domestic or international treatment, conversion charges, and any minimums or caps. A lower percentage alone does not establish which option costs less for your transaction mix.
For context, Square’s US pricing page, accessed October 4, 2026, displayed online card rates of 2.9% + $0.30 on two plans and 3.3% + $0.30 on another. Its displayed US in-person tap, dip, or swipe rates varied by plan: 2.4% + $0.15, 2.5% + $0.15, and 2.6% + $0.15. These are examples from the displayed plans and channels, not a rate that applies to every Square account or payment.
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PayPal’s US merchant fee schedule, last updated October 1, 2026, lists domestic invoice payments via standard credit or debit cards, Apple Pay, or other third-party wallets at 2.99% plus the fixed fee for the received currency. Invoice payments through PayPal Checkout, Venmo, or Guest Checkout are listed at 3.49% plus the currency-specific fixed fee. Invoice Pay by Bank (ACH) is listed at 1%, capped at $10 per transaction. The schedule also adds a separate percentage-based charge for international commercial and invoice transactions; these domestic examples do not describe cross-border costs.
See the current terms for your transaction before using an example rate in an invoice calculation: Square US processing fees and pricing and PayPal US merchant fees.
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What “net” means in this calculation
The result is your payout after processing fees, not your business profit or personal take-home pay. Profit depends on other business expenses; after-tax income depends on your personal tax circumstances. The processor fee formula does not calculate either of those amounts.
Square says its processing fees are deducted before funds are transferred to the linked bank account and are taken from the transaction total, including tax and tip. Check how your provider applies fees to the amount charged, and use its current account schedule for the relevant payment type: Square support: what are Square’s fees?
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