Who this comparison is for
Mid-market merchants where custom IC++ from independent ISOs consistently beats every retail processor — and negotiation is mandatory, not optional.
Recommended processors for $100K–$250K monthly
The 4 processors below are the ones whose published rates, contract terms, and operator-side reputation hold up at this volume. Effective rates assume a normalized U.S. SMB card mix (60% credit, 40% debit, 30% rewards). See the methodology page for full assumptions.
1. Negotiated IC++ from an independent ISO
1.85–2.15% (interchange + 0.10–0.20% + $0.08–$0.10)Custom interchange-plus-plusBest for
Default recommendation at this tier. The 3-ISO quote process pays for itself within the first 30 days.
Watch out for
Read the contract carefully — early termination clauses + liquidated damages are where ISOs claw back the negotiation discount.
2. Stax
2.13–2.21% + $199/moSubscription IC-plusBest for
Operators who value the subscription's premium support tier and do not want to negotiate.
Watch out for
At this volume, the subscription saves nothing over auto-discounted Helcim. Justify by support quality, not cost.
3. Payment Depot
2.09–2.18% + $199/moMembership IC-plusBest for
Operators on the membership-tier ladder who fit cleanly into a published bucket.
Watch out for
Between-tier costs do not amortize cleanly. Stax or Helcim usually edge it.
4. Adyen
1.91–2.04% + minimum ~$120K monthly + setup workEnterprise interchange-plusBest for
International / cross-border merchants where Adyen's unified processing across regions is unique.
Watch out for
Setup is engineering-heavy. Best for tech-forward operators with developer resources.
Pricing-model breakdown at $100K–$250K monthly
At $100K–$250K monthly monthly volume, three pricing models compete: flat-rate or auto-discount interchange-plus on the entry end, subscription interchange-plus in the middle, and custom IC++ contracts at the top. Here is the math on each.
Tier 1
Custom IC++ (default)
Negotiated through 3 ISOs
Interchange + 0.15–0.25% + $0.08–$0.10 per transaction. No monthly fee in most contracts.
Best for
$100K–$200K monthly. Best math at this volume.
What’s included
- ·Lowest available rate
- ·Negotiable contract terms (push: no ETF, no auto-renewal, capped reserve)
- ·Direct relationship with the underwriter
- ·PCI / statement / regulatory fees waivable
- ·Run the 3-quote process every 24 months at minimum
Tier 2
Subscription premium
Stax / Payment Depot
$199 monthly + Interchange + 0%–0.10% markup
Best for
$100K–$200K monthly with stable card mix and operators who value subscription predictability.
What’s included
- ·Premium support included
- ·Often free hardware
- ·Predictable monthly subscription
- ·Lowest published per-transaction markup
- ·Better fit for forecast-driven operators
Tier 3
Enterprise IC++
Adyen / Worldpay (negotiated)
Negotiated. Typically interchange + 0.10–0.15% + custom per-transaction fees
Best for
$200K–$250K monthly with international / cross-border volume or complex use cases.
What’s included
- ·Lowest rate available in U.S.
- ·Unified cross-border processing (Adyen)
- ·Direct acquirer relationship
- ·Engineering-heavy onboarding
- ·Best for mid-market with developer resources
The actual math at $100K–$250K monthly
At $175,000 monthly with a typical mid-market card mix (70% credit, 30% debit, 35% rewards) and $120 average ticket, the comparison runs: Negotiated IC++ ≈ $3,300/month (1.89% effective). Stax ≈ $199/mo + $3,710 ≈ $3,909/month (2.23% effective). Helcim with auto-discounts ≈ $3,640/month (2.08% effective). The custom IC++ route saves $300–$600/month over the next-best option, which is $3,600–$7,200/year. At this tier, not running a 3-quote process is leaving real money on the table.
Sources
- myPayAdvisor 2026 Payment Processor Effective Rate Database — open dataset, CC-BY-4.0. View
- myPayAdvisor Research Methodology — card-mix assumption, sample selection, calculation method. View
- Federal Reserve Payments Study series — U.S. SMB card-mix distribution. federalreserve.gov
- Processor public pricing pages (captured 2026-04-30): Stripe, Square, Helcim, PayPal, Stax, Payment Depot, Adyen, Worldpay, Clover, Authorize.net, Braintree, Shopify Payments.