Fee Impact Analysis on Different Invoice Sizes
See how payment processing fees affect invoices of different sizes — and why the flat fee matters more than you think.
Fee Impact on Different Invoices
See how Stripe's standard rate (2.9% + $0.30) affects invoices of various sizes
| Invoice Type | Invoice Amount | Total Fee | You Receive | Effective Rate |
|---|---|---|---|---|
| Small Project | $100.00 | -$3.20 | $96.80 | 3.20% |
| Medium Project | $500.00 | -$14.80 | $485.20 | 2.96% |
| Standard Invoice | $1,000.00 | -$29.30 | $970.70 | 2.93% |
| Large Contract | $5,000.00 | -$145.30 | $4854.70 | 2.91% |
Note: The flat fee has a bigger impact on smaller invoices. A $100 invoice loses 3.2% to fees, while a $5,000 invoice loses only 2.91%.
The Hidden Cost of the Flat Fee
Most payment processors charge a flat per-transaction fee — typically $0.30 — in addition to a percentage rate. This flat fee has a disproportionate impact on smaller invoices. On a $50 invoice, a $0.30 flat fee represents 0.6% of the total amount on top of the percentage rate, pushing your effective fee rate above 3.5%. On a $5,000 invoice, that same $0.30 is just 0.006% — practically negligible. This is why bundling small projects into a single monthly invoice can save you money: you pay fewer flat fees overall.
Comparing Processors Side by Side
Different processors have different fee structures that favor different invoice sizes. Stripe charges 2.9% + $0.30, which works well for mid-range invoices. Square charges 2.6% + $0.10, making it slightly cheaper for smaller transactions due to the lower flat fee. PayPal's standard rate is 3.49% + $0.49, which is higher overall but includes some buyer protection features. For very large invoices, the percentage rate dominates, so the processor with the lowest percentage wins. For very small invoices, the flat fee dominates, so the processor with the lowest flat fee wins. Use our calculator to compare all three processors on your specific invoice amounts.
Real-World Scenarios for Freelancers
Let's look at a realistic example. A freelance graphic designer sends five $200 invoices per week using Stripe. Each invoice incurs $6.18 in fees (2.9% + $0.30), totaling $30.90 per week or roughly $1,600 per year — just in processing fees. By switching those same payments to ACH at 0.8%, the cost drops to $8.00 per week or about $416 per year, saving over $1,180 annually. The numbers speak for themselves: understanding your fee structure and choosing the right payment method for each invoice size can have a meaningful impact on your bottom line.