Credit Card Processing Fees Explained:
A Guide for Small Businesses

Every time a customer pays with a credit or debit card, a small slice of that transaction disappears before it ever hits your account. For small businesses operating on thin margins, those fractions of a percent add up to thousands of dollars each year — often without owners fully understanding where the money goes.

The Three Layers of Card Processing Fees

Credit card processing fees are not a single charge. They're a stack of three separate costs bundled together by your payment processor:

• Interchange fee: Set by card networks (Visa, Mastercard, Amex). This is the largest portion and goes to the card-issuing bank. Typically 1.5%–2.5% for credit cards.
• Assessment fee: Charged by the card network itself (Visa, Mastercard). Usually 0.13%–0.15% — small but unavoidable.
• Processor markup: Added by your payment processor (Stripe, Square, PayPal, etc.) as their profit margin. This varies widely between providers.

Flat-Rate vs Interchange-Plus Pricing

When you sign up with a payment processor, you'll typically encounter two main pricing models:

• Flat-rate pricing: You pay one simple rate on every transaction (e.g., 2.9% + $0.30). Easy to predict, but often more expensive because the processor averages in their margin across all card types. This is how Stripe and PayPal work.
• Interchange-plus pricing: You pay the actual interchange fee set by the card network, plus a fixed markup from the processor. More transparent and typically cheaper at volume, but harder to predict month to month.

For most small businesses and freelancers processing under $10,000/month, flat-rate pricing is simpler and the price difference is minimal. As volume grows, interchange-plus becomes worth investigating.

How Card Type Affects Your Rate

Not all card transactions cost the same. The interchange fee varies significantly based on card type:

• Debit cards: Generally lower — often 0.05% + $0.22 (regulated debit)
• Standard credit cards: Around 1.51%–1.65%
• Rewards credit cards: 1.8%–2.2% — the rewards come from these higher fees
• Corporate/purchasing cards: Up to 2.5%+ due to additional benefits
• American Express: Historically 2.5–3% — has come down in recent years

When your customers pay with premium rewards cards, you're effectively subsidizing their airline miles and cashback. This is worth factoring into your pricing strategy.

The Real Total Cost: An Example

Let's say you run an e-commerce store doing $5,000/month in sales via Stripe at 2.9% + $0.30 per transaction, averaging 50 transactions/month:

• Percentage fees: $5,000 × 2.9% = $145.00
• Per-transaction fees: 50 × $0.30 = $15.00
• Total monthly processing cost: $160.00
• Annual cost: $1,920.00

That's nearly $2,000 per year — just on processing fees. Understanding this number is the first step to evaluating whether switching processors or adjusting your pricing makes sense.

Strategies to Reduce Processing Fees

• Encourage ACH/bank transfers for large transactions: Stripe's ACH rate is 0.8% capped at $5. On a $1,000 invoice, that's $5 instead of $29.30.
• Add a card surcharge (where legal): Passing the processing fee to customers is legal in most US states, though it requires disclosure and compliance with card network rules.
• Negotiate with your processor: If you process more than $50,000/month, most processors will offer custom rates.
• Consolidate transactions: Fewer, larger transactions mean fewer fixed per-transaction fees.
• Use Level 2/3 processing for B2B: Providing extra invoice data on corporate card transactions can lower your interchange rate by 0.5–1%.

Use our PayPal Fee Calculator and Stripe Fee Calculator to compare real costs across different transaction amounts before choosing a processor.