Payment Processing Hub — San Diego payment guidance

How Credit Card Processing Fees Work

Most business owners are paying more than they should — not because they got ripped off, but because nobody explained how the fee structure actually works. Here’s the plain-language version.

💵 The Three Layers of Processing Fees

1. Interchange — The wholesale cost set by Visa/Mastercard/Amex. Goes to the card-issuing bank. Non-negotiable. Ranges from ~0.05% (debit, regulated) to 2.4%+ (premium rewards cards). This is the floor every processor pays.

2. Assessment fee — A small network fee charged by Visa/Mastercard/Discover directly. Typically 0.13–0.15% per transaction. Also non-negotiable.

3. Processor markup — What your payment processor adds on top of interchange + assessment. This is the only part that’s negotiable. It can be structured as flat-rate, tiered, or interchange-plus.

The key insight: When Square charges you 2.6% + 10¢, that single number bundles all three layers together. When an ISO quotes you “interchange + 0.25% + 10¢,” they’re showing you only their markup — the total effective rate is interchange + their markup.

📊 Flat-Rate vs Interchange-Plus vs Tiered

Pricing ModelHow It WorksWho It FavorsTransparency
Flat-Rate
(Square, Stripe)
One rate for everything — e.g. 2.6% + 10¢ regardless of card typeLow-volume or mixed card typesSimple, but you can’t see your real wholesale cost
Interchange-Plus
(I+)
Actual interchange cost + fixed processor markup — e.g. IC + 0.30% + 15¢Medium-to-high volumeFull visibility into wholesale cost vs markup
Tiered / Bundled
(Legacy ISOs)
“Qualified,” “mid-qualified,” “non-qualified” buckets. Downgrade fees apply.Mostly the processorVery low — hard to audit or compare
Subscription
(Stax, Helcim)
Fixed monthly fee + interchange only — no per-transaction markup percentageHigh-volume businessesVery high — pure wholesale cost + flat fee

⏱ Settlement Timing — When Does Money Actually Arrive?

  • Same-day / instant: Square Instant Transfer (1.75% fee), Stripe Instant Payout (1% fee). Money in minutes.
  • Next-day (T+1): Standard with Square, Stripe, PayPal for most accounts in good standing
  • 2-business-day (T+2): Common with traditional merchant accounts and Clover
  • Weekly batch: Some legacy processors still batch on Fridays only — a cash flow problem
  • Manual release / holds: New accounts or high-risk categories may have funds held for 30–90 days pending review
Practical rule: If your processor holds funds for more than 3 business days on a regular basis and you process more than $5,000/month, the cash flow cost of that delay is worth calculating before your next contract renewal.

🚫 Hidden Fees That Don’t Show on the Rate Card

  • Batch fee: $0.05–$0.25 per day you run a batch of transactions — adds $18–$90/year
  • Statement fee: $5–$15/month even if you never open the PDF
  • PCI non-compliance fee: $30–$100/month if you haven’t completed the annual PCI questionnaire
  • Chargeback fee: $15–$35 per dispute, win or lose
  • Early termination fee (ETF): $200–$500 or “liquidated damages” clauses that multiply remaining months × average monthly fees
  • Downgrade / non-qualified surcharge: Tiered pricing’s trap — rewards cards and manually-keyed transactions often “downgrade” to a higher category
  • IVR / voice authorization fee: $0.50–$1.50 per call — charged when you call in a card number instead of swiping

💰 What You Should Be Paying by Volume

  • Under $5,000/month: 2.5–2.9% effective rate is normal. Flat-rate simplicity makes sense at this volume.
  • $5,000–$15,000/month: Ask any processor for interchange-plus pricing. Target under 2.5% effective rate.
  • $15,000–$50,000/month: You have negotiating leverage. Target 1.8–2.2% effective rate. Multiple ISOs should compete for your business.
  • Over $50,000/month: Consider a subscription-model processor (Stax, Helcim) or negotiate directly with a bank acquirer. Sub-1.8% is achievable.

Not Sure What You’re Actually Paying?

Text PJ your last processing statement. We’ll calculate your real effective rate and tell you whether you’re overpaying — in plain language, no sales pitch.

Text PJ — 773-544-1231

❓ Frequently Asked Questions

Why do rewards cards cost more to process?

Premium cards (Visa Signature, Amex Platinum, etc.) have higher interchange rates because the card network funds the rewards program from that interchange. A regular Visa debit card might cost 0.05% + 22¢ in interchange. A Visa Infinite rewards card costs 2.10% + 10¢. On flat-rate pricing, you pay 2.6% for both. On interchange-plus, you see the actual difference.

What is a chargeback and how do I avoid them?

A chargeback is when a customer disputes a charge with their bank directly, bypassing you. The bank provisionally refunds the customer and debits your account. You have ~7–30 days to respond with evidence. To reduce chargebacks: use clear business name descriptors on statements, get signed receipts, use AVS for card-not-present, and respond to every dispute even if you’re likely to lose — a pattern of non-response worsens your chargeback ratio.

What is PCI compliance and do I actually need it?

PCI DSS (Payment Card Industry Data Security Standard) is a set of security requirements for any business that stores, transmits, or processes cardholder data. If you take cards, you need to complete an annual Self-Assessment Questionnaire (SAQ). Most small businesses using a hosted payment page or Square/Stripe terminal are SAQ-A (simplest level). Non-compliance fees are a pure processor profit center — complete the questionnaire and the fee disappears.

Is it worth switching processors mid-year?

Run the math: (current effective rate − new effective rate) × annual volume = gross savings. Subtract ETF + setup time + hardware cost. For most businesses processing $15,000+/month, the savings exceed switching costs within 3–6 months. If you’re under $5,000/month, the savings are usually under $50/month — probably not worth the admin overhead.

What does “effective rate” mean?

Your effective rate is total fees paid ÷ total volume processed, expressed as a percentage. It’s the only honest way to compare processors because it accounts for all fees (transaction fees, monthly fees, batch fees). To calculate it: find your monthly statement, divide total fees by total sales volume, multiply by 100.

Can I pass processing fees to customers (surcharging)?

In California, surcharging is legal under certain conditions: you must disclose it at the point of entry and point of sale, the surcharge can’t exceed your actual cost, and debit card surcharges are federally prohibited. Many San Diego businesses add a “cash discount” program instead — list a slightly higher price and give a discount for cash, which achieves the same economic result without the surcharge disclosure rules.

🔗 Related Guides

Text PJ — 773-544-1231

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Updated: 2026-02-23