Billing the gateway fee to your client

When a client pays you by card or in a foreign currency, the gateway takes its cut from the total before the money reaches you. The convention in most freelancing markets has been to absorb that silently — and to undercharge by exactly the cost of every transaction. There is a cleaner convention: bill the processing cost as a transparent line item on the invoice, so the client sees what the payment costs and your net is exactly what you quoted.

What the buffer needs to cover

A complete fee buffer covers three things, not one. The processing percentage (2.9% plus $0.30 for Stripe cards, 3.49% plus a fixed fee for PayPal, up to 4.4% cross-border), the fixed per-transaction fee, and — if the invoice is in a different currency than your receiving account — the hidden FX markup (about 1% for Stripe, 3.9% for PayPal, ~1.3–2% for Payoneer on many corridors). A buffer that only covers the percentage leaves you short on the fixed fee and the spread every single time.

The math that makes it fair

The trick is that the buffer has to be calculated on the total including itself — otherwise the gateway's percentage fee is charged on the buffer too, and you come up short by a few cents on every invoice. The correct gross is: your net divided by one minus the total fee rate, then the fixed fee added. Most people round this up to a clean number. PayUtility's forward fee calculator does exactly this in reverse for you: enter the gross and see the net, or use the reverse invoice calculator to start from the net you want and get the gross that survives every fee.

What the line item looks like

On the invoice, the buffer appears as a separate row — "Processing fee (2.9% + $0.30)" or "Payment processing & currency conversion" — so the client sees both your base rate and the cost of the payment method. The PDF invoice builder generates this automatically: it computes the gateway cost on a chosen corridor, adds the buffer line, and produces a clean print-ready PDF with optional GST/VAT and a net total that matches what actually lands in your account. The client is rarely surprised — they already know cards cost money — and you stop treating your margin as the place where payment fees hide.

When to use it, and when not to

The buffer works best for invoices above a few hundred dollars where a percent or two is invisible in the total, and for international clients who already expect payment costs. For tiny invoices or extremely price-sensitive local clients, it can be simpler to fold the cost into your base rate and never mention it. Either way, the important discipline is the same: know your real net per invoice before you send it. Fees are estimates, so confirm live pricing — but never leave a margin at the mercy of a gateway again.