Should your small business accept Amex? For decades the answer was a reflexive no, because American Express charged merchants noticeably more than Visa or Mastercard. That advice is now mostly out of date. On flat-rate providers like SumUp, Square and Zettle, an Amex payment costs you exactly the same as any other card, which quietly kills the main argument against it. Here is the full picture on Amex fees in the UK, and who should still think twice.
Why small businesses learned to fear Amex
The old wisdom had a real basis. American Express runs its own card network end to end, issuing the cards and processing the payments itself, so it sits outside the Visa and Mastercard interchange system and sets its own merchant pricing. Historically that pricing ran noticeably higher than the equivalent Visa or Mastercard cost.
On top of the cost, acceptance used to be a separate hassle: a separate agreement, sometimes separate settlement, and a separate line on the statement. For a busy shop owner, the rational response was a polite sign in the window and a suggestion to pay another way.
That world shaped a generation of advice, and the advice outlived the world. The question worth asking in 2026 is not whether Amex used to be expensive, but what it costs on the machine sitting on your counter today.
The flat-rate reality: Amex now costs the same as Visa
Here is the genuinely good news for small businesses. Flat-rate providers charge one rate for every card they accept: SumUp at 1.69%, Square and Zettle at 1.75%. That single rate applies to Amex just as it does to Visa and Mastercard, so a £100 Amex payment costs you £1.69 on SumUp, exactly the same as a £100 Visa debit tap.
This is one of the few places where the flat-rate model quietly hands small merchants a win that big merchants do not automatically get. The provider absorbs the difference in underlying network costs and averages it across everyone, which means the historically priciest card arrives at your till costing nothing extra.
The practical consequence: if you are on a flat-rate reader and still refusing Amex, you are turning away sales to avoid a surcharge that no longer exists. That is not thrift, it is habit.
Who actually carries Amex, and why it matters
Amex cardholders skew towards higher spenders: rewards chasers, frequent travellers, and corporate cardholders whose company pays the bill. These are customers who tend to spend more per visit and think less about the total, which is precisely the customer most small businesses want more of.
Corporate Amex cards deserve a special mention. If you sell to business customers, whether catering, trade supplies or client lunches, a chunk of your buyers may be reaching for a company Amex first. Refusing it introduces friction at the exact moment someone is trying to give you money.
We will not invent statistics about how much more Amex holders spend, because the honest point does not need them: the card sits disproportionately in the wallets of people with money to spend, and accepting it removes a reason for them to walk out.
Amex fees on traditional acquirers: still a separate conversation
If you are with a quote-based acquirer such as Dojo, Worldpay or Tyl, the old rules still partly apply. Amex acceptance is typically priced separately from your Visa and Mastercard rates, often via Amex's own small-merchant programme, and the rate you get depends on your business and your negotiation. We will not quote their rates because they genuinely vary; check current terms on your own agreement.
That means traditional-acquirer merchants still need to do arithmetic. If your negotiated Visa rate is well under 1%, an Amex rate materially above it makes each Amex sale genuinely more expensive, and the question becomes whether the extra sales cover the extra margin. Our guide to card machine fees covers how to read those statements.
Settlement timing can also differ on separate Amex agreements, so if cash flow is tight, ask the question before signing rather than after. None of this is a reason to refuse Amex outright; it is a reason to price it knowingly.
The no-Amex sign is a lost-revenue sign
Every payment method you refuse is a small tax on your own turnover. Some Amex customers carry a backup Visa and will grumble and pay; some will quietly buy less; a few, especially corporate spenders locked to a company card, simply cannot pay you at all. You never see the sales that do not happen, which is what makes the sign feel free.
The cost-benefit has flipped on flat-rate readers. When Amex cost you visibly more per transaction, refusing it was a defensible margin decision. Now that it costs the same as Visa on SumUp, Square and Zettle, the sign in the window protects you from nothing and filters out your best-spending customers.
Who should still say no: a traditional-acquirer merchant quoted a genuinely painful Amex rate on thin margins, selling to customers who rarely carry the card. That is a real case, and it is fine. It is also increasingly rare.
How to switch on Amex acceptance
On flat-rate providers there is usually nothing to switch on: SumUp, Square and Zettle accept Amex out of the box at their standard rate, so your reader already takes it. If in doubt, run a test transaction or check the accepted-cards list in your dashboard.
On a traditional acquirer, ask your provider to add Amex acceptance. Smaller merchants are typically set up through a programme where Amex payments arrive through your existing terminal and settlement, while larger ones may get a direct Amex agreement with its own MID and statement. Ask which you are getting and what the rate is, and check current terms.
Then tell people. Put the Amex logo back on the door and by the till, because customers who have been refused before will not assume anything changed. If you are still choosing a provider, compare card machines with Amex pricing as one of your columns.
The verdict
For the large majority of UK small businesses on flat-rate readers, accepting Amex in 2026 is a no-brainer: same fee as Visa, higher-spending customers, zero extra admin. The old advice was right in its day, and its day is over.
If you are on a negotiated acquirer deal, get the Amex rate in writing and do the sums against your average sale before deciding, using our fee calculator if it helps. Refusing Amex should be the output of arithmetic, not a tradition inherited from 2009.
FAQs
Should a small business accept Amex in the UK?
Usually yes. On flat-rate providers like SumUp, Square and Zettle, Amex costs exactly the same as Visa or Mastercard, so there is no fee penalty for accepting it. The main exception is a traditional-acquirer merchant quoted a high separate Amex rate on thin margins.
How much are Amex fees for UK small businesses?
On flat-rate readers, the same as any other card: 1.69% on SumUp and 1.75% on Square and Zettle. On quote-based acquirers like Dojo or Worldpay, Amex is priced separately and varies by business, so check current terms on your own agreement.
Why do some businesses still not take Amex?
Mostly habit from the era when Amex genuinely cost more, plus some traditional-acquirer merchants who still face a higher negotiated Amex rate. For anyone on a flat-rate reader, the cost argument no longer applies and refusal just turns away higher-spending customers.
How do I start accepting Amex payments?
On SumUp, Square or Zettle it is already enabled at the standard flat rate, so your reader takes Amex today. On a traditional acquirer, ask your provider to add Amex acceptance, confirm the rate and settlement arrangements in writing, then display the Amex logo so customers know.
