I keep a small worksheet habit for proposals that will settle on Stripe. The trap is quoting a round “you pay $X” number and then discovering the processing cut and any international extras leave the studio short. A fee calculator pass before the proposal goes out is boring and worth it.
- Base percentage plus fixed per-charge fee
- Currency conversion or cross-border add-ons when relevant
- Refunds and disputes as rare but expensive events
- Whether the client pays gross or you absorb fees
If you absorb fees, your proposal price needs headroom. If the client pays gross, say so in one plain sentence so finance does not argue later.
1. Decide the net you need after tools and taxes (separate from Stripe).
2. Run the charge amount through a Stripe fee estimate.
3. Round in the direction that protects net, not the direction that looks prettier.
4. Write the assumption under the price (“card processing estimated via Stripe standard US rates; international cards may differ”).
5. Recompute if the scope changes by more than a small delta.
Mental math fails when fixed fees meet odd totals. A $997 invoice and a $1,000 invoice do not feel different until the fixed component and percent interact with discounts. Calculators also make it easy to compare “charge $X to net $Y” versus “net $Y requires charging $Z.”
Put the fee assumption near the payment schedule, not buried in a footer. If you use payment links, test one live charge on a small invoice so the dashboard totals match your worksheet. When a client insists on a wire instead, recompute; the fee story changes and so should the quote language.
For a quick estimate before a proposal leaves the desk, I use a Stripe fee calculator and paste the assumption line into the SOW. It will not replace your accountant, but it stops the “we forgot the cut” email after kickoff.
Cross-border cards, currency conversion, and billing-interval experiments change the effective cut. If you sell in multiple currencies, estimate each currency path. For subscriptions, model failed payments and retry behavior qualitatively even if the calculator is charge-centric; cash flow risk is part of fee reality. When you add tax inclusive pricing, decide whether tax sits inside or outside the fee base according to your region and tools.
“Estimated card processing is included in this quote using standard Stripe pricing assumptions current as of [month]. Instant payouts, international cards, or dispute costs are not included.” That paragraph is dull and prevents a certain class of angry email. Update the month when pricing pages change.
Have a second person spot-check the arithmetic on invoices above a threshold. Most errors are transcription errors, not conceptual ones. A calculator helps only if the inputs you type match the deal you signed.
Net target set, fee estimate captured, assumption sentence written, second person spot-check on large invoices, dashboard test charge done once per setup change. If marketing wants a prettier round number, adjust intentionally and recompute rather than silently absorbing a cut. Pretty numbers that destroy net are not pretty. Revisit the checklist when you add a new currency or a new tax tool, because those changes quietly move the fee base. Keep the checklist in the proposal template repository so it is harder to “forget this time.”