UK In-Person Payments: Square vs. SumUp vs. iZettle (Which Is Actually Cheapest?)
- The UK Payment Processor Confusion
- Why UK Processors All Charge Same Headline Rate
- AskBiz True Cost Comparison
- Real Example: UK Pop-Up Retail
- Chargebacks and Disputes: The Cost Nobody Compares Until It Happens
- Hardware Costs and Contract Lock-In: The Fee You Pay Once But Feel for Years
- Settlement Speed Matters More Than Retailers Realise
- A Second Scenario: The Mobile Trader Without Reliable Signal
UK in-person payment processors all claim "1.69%" as their headline rate. But: SumUp charges £20/month subscription (hidden). Square charges for invoicing (£1 per invoice). iZettle has no add-ons. True cost: SumUp 1.87% (if 1,000 transactions/month), Square 1.78%, iZettle 1.69%. iZettle wins, but most retailers don't know.
- The UK Payment Processor Confusion
- Why UK Processors All Charge Same Headline Rate
- AskBiz True Cost Comparison
- Real Example: UK Pop-Up Retail
- Chargebacks and Disputes: The Cost Nobody Compares Until It Happens
The UK Payment Processor Confusion#
Three main in-person processors: (1) Square: 1.69%, no monthly fee, charges for invoices. (2) SumUp: 1.69%, £20/month subscription. (3) iZettle: 1.69%, no fees. All advertise "1.69%" as if equal. But: Square charges £1 per invoice (small merchants send 50/month = £50 extra). SumUp charges £20/month (£240/year). iZettle charges nothing. On £100K annual sales: (1) Square: £1,690 + £600 invoicing = £2,290 (2.29%). (2) SumUp: £1,690 + £240 = £1,930 (1.93%). (3) iZettle: £1,690 (1.69%). iZettle is 36% cheaper than Square, but most don't know.
Why UK Processors All Charge Same Headline Rate#
Interchange rates (Visa/Amex charges) are fixed by card networks. So all processors have the same baseline cost. They compete on add-ons and hidden fees, not headline rate. Consumers focus on headline rate, so processors make it identical and hide the real costs in subscriptions/add-ons.
AskBiz True Cost Comparison#
AskBiz inputs: (1) Your monthly transaction count. (2) Use of invoicing, reporting, etc. (3) Payment mix (card-present vs. online, if applicable). Output: True cost on Square, SumUp, iZettle with all fees included. Example: "You do 2,000 card-present transactions + 100 invoices/month. Square cost: 2.29%. SumUp: 1.93%. iZettle: 1.69%. Recommend: iZettle (save £1,200/year)."
Real Example: UK Pop-Up Retail#
A pop-up retail store did 5,000 card-present transactions per month (customers only pay by card). Used Square because "well-known." Paid: 1.69% + invoicing fees (for back-office work). True cost: 2.1%. Switched to iZettle (same reader compatibility). True cost: 1.69%. Savings: 0.41% on £300K annual sales = £1,230/year.
Chargebacks and Disputes: The Cost Nobody Compares Until It Happens#
Headline processing rates get all the attention in payment provider comparisons, but for a retailer selling higher-value goods, chargeback and dispute handling can matter more to the bottom line than half a percentage point of transaction fee. When a customer disputes a card payment — claiming non-delivery, an unauthorised transaction, or goods not as described — the processor's dispute process determines how much evidence you need to provide, how quickly you need to respond, and crucially, whether a chargeback fee is levied regardless of the outcome. Some providers charge a flat administration fee simply for a dispute being raised, win or lose, while others only charge if the merchant loses the case. A furniture restorer or independent jeweller processing occasional high-value transactions faces materially more chargeback risk per transaction than a coffee cart processing hundreds of small transactions a day, simply because higher-value disputed transactions attract more scrutiny and more determined disputing customers. A retailer who chose their processor purely on the lowest percentage rate, without checking the dispute fee structure, can find that a single contested high-value sale wipes out a full month's savings from the marginally cheaper rate. For any retailer whose average transaction value sits meaningfully above the low tens of pounds, dispute handling terms deserve as much scrutiny as the headline percentage.
Hardware Costs and Contract Lock-In: The Fee You Pay Once But Feel for Years#
The card reader itself is rarely free, and how it is paid for varies significantly between providers in ways that affect total cost of ownership well beyond the transaction fee percentage. Some providers sell the reader outright for a one-off upfront cost, after which it is simply owned equipment. Others offer it at a lower or subsidised upfront price but attach a minimum contract term, meaning a retailer who wants to switch providers within that period faces an early termination cost or simply has to accept a slower payback on hardware they have not finished paying off. Still others lease hardware on a rolling monthly charge that never converts to ownership, which can look attractive for cash-flow reasons in month one but becomes the more expensive option over an eighteen-month or two-year horizon. A retailer comparing three quotes purely on percentage-per-transaction can easily miss that one provider's seemingly generous free-reader offer is bundled with a twelve-month minimum term, while a competitor's higher upfront hardware cost comes with no lock-in at all — meaning the retailer who values flexibility to renegotiate or switch providers as their business grows is paying a real, if hidden, price for that flexibility with the "free" reader option. Reading the actual contract term, not just the monthly or per-transaction rate, is essential before signing.
Settlement Speed Matters More Than Retailers Realise#
How quickly a payment provider actually deposits card takings into a retailer's bank account is a cash-flow factor that rarely appears on a comparison chart but can matter enormously to a small, tightly-margined business. Some providers settle funds the next business day as standard; others take two to three business days, and some offer faster settlement only as a paid add-on. For a retailer with healthy cash reserves, a few days' delay in receiving takings is a minor inconvenience. For a retailer running close to the edge — paying suppliers, staff wages, or rent out of the same account that card takings land in — a two-to-three-day settlement delay can be the difference between making a payment on time and incurring a late fee or supplier friction, particularly around weekends and bank holidays when settlement windows can stretch further than the headline "next-day" promise suggests. A market trader or small independent shop operating on thin working capital should weigh settlement speed as seriously as the percentage rate, because the practical cost of a cash-flow gap — an overdraft fee, a missed early-payment supplier discount, a bounced direct debit — can easily exceed the difference in processing fees between providers over the course of a month.
A Second Scenario: The Mobile Trader Without Reliable Signal#
Fee comparisons assume a stable environment, but a meaningful share of UK small businesses operate somewhere that assumption breaks down. A mobile hairdresser visiting clients at home, or a trader working a rural farmers' market with patchy mobile signal, has a different priority list entirely: reliability of connection and offline transaction handling matter more than a tenth of a percentage point of fee. Some card readers rely entirely on a live data connection to authorise every transaction and simply fail in a signal dead zone, forcing the trader to either lose the sale or resort to awkward workarounds like asking the customer to pay by bank transfer on the spot. Others offer offline transaction capability, queuing and processing payments once connectivity returns, which for a trader working the same low-signal locations week after week is the difference between a normal trading day and a day of lost sales. A farmers' market trader who switched from a well-known low-fee provider to a slightly more expensive alternative specifically because the second reader handled patchy 3G reliably reported the switch paid for itself within a single market season, purely through sales that would otherwise have been lost to a stalled terminal. For traders in this position, the right comparison question is not "which is cheapest" but "which one actually works reliably where I trade," with cost as the second filter rather than the first.
People also ask
Do I need a monthly subscription for in-person payments?
Not necessarily. iZettle and Square don't require it. SumUp does (£20/month). Choose based on your volume.
Can I use multiple processors?
Yes. Use iZettle for card-present, Stripe for online. But complicates reconciliation. Pick one if possible.
Are there cheaper processors than 1.69%?
PayPal Here: 1.5%, but limited features. Most mainstream processors: 1.69-2%. Small difference for small merchants.
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