The short answer
Your processor's markup is whatever they charge you on top of the two fixed costs that pass straight through to the card networks: interchange (paid to the issuer) and network assessments (paid to the network). On an interchange-plus statement, the markup is explicit: "0.25% + $0.10 over interchange." On a flat-rate or tiered statement, it's blended into the single rate you see and you have to back it out yourself.
How to back out the markup on a blended rate
If your flat-rate processor charges 2.9% + $0.30, and your portfolio's blended interchange runs around 2.1% + $0.12, and network assessments are 0.14%, the math is:
Markup = 2.9% - 2.1% - 0.14% = 0.66%
Plus: $0.30 - $0.12 = $0.18 per transaction
On $100k/mo in volume averaging $85 per order, that's 1,176 transactions × $0.18 = $211.68, plus 0.66% × $100k = $660. Total monthly markup: $871.68. Annualized: $10,460.
Benchmarks by volume tier
- $0-$30k/mo: 50-80 bps + $0.15-$0.30. You're on flat-rate; the processor needs the margin.
- $30k-$100k/mo: 30-50 bps + $0.10-$0.15. Interchange-plus becomes available; processors start competing.
- $100k-$500k/mo: 18-30 bps + $0.07-$0.12. You have leverage; processors will sharpen for your volume.
- $500k-$2M/mo: 10-18 bps + $0.05-$0.10. Tier-1 acquirer territory; you're a named account.
- $2M+/mo: 6-12 bps + $0.04-$0.08. Strategic pricing; you're negotiating directly with acquirer relationship managers.
What operators need to know
- Markup is the whole conversation. Interchange and assessments are the same for every processor. When you're comparing Stripe to your IC+ option to a high-risk acquirer, you're comparing markup, not total cost.
- Markup moves on volume, not promises. Processors sharpen pricing when you demonstrate volume, not when you project it. Most will rerate at 90 days if you beat your projection.
- Per-transaction markup kills small tickets. A $0.30 per-transaction fee is 3% of a $10 order. For subscription businesses with micro-transaction fees, optimize the per-txn number as hard as the percentage.
- Hidden markup exists too. Downgrade surcharges, batch fees, PCI fees, statement fees, monthly minimums — all of these are markup wearing different names. See true-cost effective rate.
- Markup is reviewable. A good processor will re-quote you annually as your volume grows. If yours won't, that's your signal to shop.
Why multi-brand operators care
Running 4 brands at $80k/mo each on 4 separate processors means 4 separate markup stacks at the $30-$100k/mo tier — roughly 40-50 bps each. Consolidating that $320k/mo on a single parent merchant account pulls you into the $100-$500k tier, where 22-30 bps is the benchmark. The difference is $60k-$85k/yr in margin that flows directly to your P&L. See our multi-brand savings calculator.