Card Machine Fees UK 2026: SumUp vs Zettle vs Square vs Stripe Compared

Written by Calvin Lo, Founder of Aphelios Software | July 2026 | 8 min read

If you are comparing card machines for your UK business, the headline transaction fee is only half the story. The cost of accepting card payments depends on the transaction rate, the price of the reader, monthly fees, and the charges that hide in the small print: American Express rates, refund fees and paid plans.

In this guide we break down what card machine fees actually cost UK small businesses in 2026, compare SumUp, Zettle, Square and Stripe, and show why some businesses end up paying more than they need to when they buy a card machine and a separate software subscription.

Card Machine Fees at a Glance (2026)

SumUp Fees: The Low-Cost Standard

SumUp charges a flat 1.69% per transaction, the lowest standard rate of the three big card reader brands. The app and basic invoicing are free, and readers start at around £29. SumUp also offers a paid plan that lowers the transaction rate further, which is worth it if you process high volumes.

Zettle Fees: PayPal's Simplicity

Zettle, owned by PayPal, charges 1.75% per transaction with no monthly fee for the basic plan. It is a strong choice if you already use PayPal, but the transaction rate is slightly higher than SumUp's, and the free app's inventory features are basic.

Square Fees: The Ecosystem

Square also charges 1.75% per transaction and is famous for its free POS software. However, advanced inventory, multi-location support and deeper reporting sit behind paid plans, so the true cost rises once you outgrow the free tier.

Stripe Fees: What Aphelios Uses

Stripe's UK standard rate is 1.5% plus 20p per transaction, with cards, Apple Pay, Google Pay and QR payments all supported. Aphelios processes payments through Stripe, so you get that rate without buying a card reader: any phone, tablet or computer becomes a checkout.

There is a software subscription, from £29.99/month, but it replaces the separate costs most businesses already pay: a card machine subscription, inventory software, CRM and invoicing tools. When you add those together, Aphelios is often the cheaper overall route.

The Hidden Fees Nobody Talks About

• American Express: Amex rates are usually much higher than Visa or Mastercard (often 2-3%), and some providers charge extra to accept it at all.
• International cards: Foreign-issued cards typically attract higher fees, which matters at tourist-heavy markets and events.
• Refunds: Most providers do not refund the transaction fee when you issue a refund, so heavy-refund businesses (clothing, events) pay more than they expect.
• Paid plans: SumUp, Square and Zettle all push paid plans that add features: check whether the features you need actually require the subscription.
• Hardware: Readers need replacing, and lost or damaged readers cost £29-£199 to replace.

How to Choose: Card Machine or All-in-One Platform?

A card machine makes sense if:

• You only take a handful of card payments per week
• You track stock in a spreadsheet (or not at all)
• You do not want any monthly software cost

An all-in-one platform like Aphelios makes sense if:

• You sell physical products and need real-time inventory
• You run multiple locations and need stock to sync
• You already pay for separate inventory, CRM or invoicing tools
• You want QR checkout and no hardware to buy, break or replace

The right answer depends on your volume and your operations: not just the headline percentage. For a deeper feature-by-feature comparison, see our guide to SumUp vs Zettle vs Square vs Aphelios. Use the 14-day free trial to see whether Aphelios replaces your whole stack for less than you pay today.