What it means
When a customer pays with plastic or a smartphone, several behind-the-scenes companies make the transaction happen. These include the customer's bank, your business bank, and the payment network.
The merchant fee pays for this service and usually consists of a fixed per-transaction charge plus a small percentage of the total sale amount. For non-finance managers, understanding this fee is vital because it directly impacts your profit margins on every single item sold.
Different payment methods carry very different costs. For instance, basic debit cards are typically cheaper to process than high-reward credit cards or corporate cards.
Online payments often incur higher fees than in-person chip-and-pin transactions because the risk of fraud is greater. If you do not track these costs carefully, you might find that certain low-margin products actually lose money once card processing expenses are deducted.
Businesses manage merchant fees in a few practical ways. Some negotiate volume discounts with their payment provider if they process a high number of sales.
Others encourage customers to use cheaper payment methods, such as direct bank transfers or cash, by offering small loyalty perks. When setting retail prices, smart managers factor these processing costs into their baseline pricing strategy to protect their bottom line.
Ignoring merchant fees is a common trap for growing businesses. As sales volume increases, these seemingly tiny percentages consume thousands of pounds of revenue each year.
Regularly reviewing your merchant service agreements ensures you are not overpaying and helps keep your operational costs under tight control.
In practice
Real-world examples.
Example
A local coffee shop sells a latte for £4.00. Their card processor charges a merchant fee of 1.5 percent plus 10p per transaction, meaning they pay 16p to process the sale and keep £3.84.
Example
An online boutique processes a £100 clothing order. Because it is an online transaction, the merchant fee is 2.2 percent plus 20p, costing the business £2.40 for that single sale.
Example
A small consultancy firm takes a £1,500 project deposit via a corporate credit card. Their merchant fee rate for high-value cards is 2.5 percent, resulting in a £37.50 charge.
Think of it
“Think of a merchant fee like a small toll you pay to a courier service for delivering money securely from your customer's pocket directly into your safe.
Formula
Calculation
Merchant Fee = (Transaction Amount x Percentage Rate) + Fixed Per-Transaction Fee
Example: If you sell £1,000 worth of goods in a month, and your agreed rate is 2 percent plus 10p per transaction across 50 individual sales:
Percentage Cost = £1,000 x 0.02 = £20
Fixed Cost = 50 sales x £0.10 = £5
Total Merchant Fee = £20 + £5 = £25Case study
Seen in the real world.
BrightBake Bakery noticed strong revenue growth over six months, but their net profit remained surprisingly flat. The owner, Sarah, decided to investigate the operational expenses and discovered that merchant fees were quietly eroding her profits. BrightBake processed around 4,000 card transactions every month, averaging £12 per sale. Their current payment provider charged a flat 2.8 percent on every transaction with no fixed fee.
Sarah calculated that on £48,000 of monthly revenue, she was paying £1,344 every month just to accept card payments. She shopped around and found a new payment provider offering a tiered rate of 1.2 percent plus 10p for debit cards, and 2.2 percent plus 10p for credit cards. Since most of her local customers used debit cards, the blended rate dropped significantly.
After switching providers and implementing a minimum card spend of £5 for purchases, BrightBake reduced their monthly merchant fees to £720. This simple review saved the bakery over £7,000 a year, directly boosting their annual profit without needing to raise prices or increase sales volume.
Watch out
Common mistakes.
- Assuming all payment processors charge the same flat rate.
- Forgetting to include merchant fees in product pricing calculations.
- Failing to review and renegotiate processing contracts as business volume grows.
Questions
People also ask.
Can I pass the merchant fee directly to the customer?
In many regions and under specific payment network rules, surcharging customers is heavily regulated or prohibited. It is usually better to factor these costs into your standard product pricing.
Why are online card payments more expensive than in-person payments?
Online transactions carry a higher risk of fraud because the physical card is not present, which means processors charge higher fees to cover that increased risk.
How can I lower my merchant fees?
You can shop around for better provider rates, encourage customers to use debit cards instead of premium credit cards, or negotiate a better deal based on high sales volume.
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