SumUp vs Square: POS System & Payment Platform Comparison for UK Small Businesses

SumUp and Square occupy similar positions in the UK small business payment market. Both are FCA authorised. Both offer card readers, free POS software, online selling tools, appointment booking, loyalty programmes, and business funding. Both serve millions of merchants globally. On the surface, they look very similar. In practice, the differences matter a great deal.

SumUp has built its UK offering around financial management: a free business bank account with a Mastercard, next-day payouts even at weekends, Making Tax Digital support in partnership with Sage, and a Payments Plus plan that drops the in-person transaction rate to 0.99% for busy merchants. SumUp charges a £10 non-refundable fee per chargeback dispute.

Square has built its offering around commerce breadth: dedicated POS systems for restaurants, retailers, and appointment businesses; an online store with Clearpay BNPL; a full developer API; a 2-year hardware warranty; and £0 chargeback fees. Its transaction rate is slightly higher than SumUp’s, but it covers more commercial ground in a single platform.

This guide covers every meaningful difference between the two — fees, hardware, software, security, regulation, and who each platform genuinely suits. All data comes directly from both providers’ UK websites, cross-checked in August 2026.

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Introduction: Two Platforms That Cover the Most Ground

SumUp and Square are both well-established, FCA-authorised payment technology companies serving UK small businesses. Both started with card readers and have expanded into complete business management platforms — covering point of sale, invoicing, online stores, appointment booking, loyalty programmes, and business funding. For many businesses, the core feature set of both platforms will be similar enough that the decision comes down to specific differences in fees, financial tools, and commerce capabilities.

The key divide: SumUp has built its platform around financial management and merchant banking — a free business bank account with a sort code, next-day payouts seven days a week, and Making Tax Digital compliance. Square has built its platform around commerce breadth — specialised vertical POS systems for restaurants, retailers, and service businesses, a developer API, and Clearpay BNPL. Understanding that fundamental difference is the starting point for choosing between them.

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At a Glance

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About SumUp

SumUp was founded in 2012 and has grown into one of Europe’s most established payment technology companies. SumUp Payments Limited is authorised by the Financial Conduct Authority under the Electronic Money Regulations 2011, FCA register number 900700. As an electronic money institution, it issues e-money accounts with account numbers and sort codes, provides payment services, and safeguards customer funds in segregated accounts that are never lent or reinvested.

As of August 2026, SumUp serves over 4 million merchants worldwide. Its UK product suite includes multiple card readers, a dual-screen POS Register, Tap to Pay, a free Business Account with a Mastercard, invoicing, payment links, an online store, appointment bookings, loyalty tools, gift cards, a merchant cash advance, and Making Tax Digital support in partnership with Sage.

SumUp’s Payments Plus plan at £19/month reduces the in-person transaction rate to 0.99% for domestic consumer cards. Custom Tailored pricing is available from £10,000 per month — a lower threshold than Square’s. SumUp charges a £10 non-refundable fee per chargeback dispute.

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About Square

Square was founded in 2009 in San Francisco by Jack Dorsey and Jim McKelvey and is owned by Block, Inc. (NYSE: SQ). In the UK it operates through Squareup Europe Ltd, registered in England and Wales (company number 08957689) and FCA authorised under the Electronic Money Regulations 2011 (FRN 900846).

Square’s UK product suite is built around commerce verticals: Square for Restaurants, Square for Retail, Square Appointments, and the Square Kiosk for self-service ordering. Square also offers free invoicing, free payment links, a virtual terminal, a full online store, Clearpay BNPL, marketing tools, team management, loyalty and gift cards, and a developer API with an extensive App Marketplace. Square charges £0 for chargebacks. Hardware instalment plans make the £699 Register available at £59/month over 12 months.

Square Loans — its business lending product — is explicitly not FCA regulated, as stated on Square’s own UK website.

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Fees: The Full Picture

Both SumUp and Square use flat-rate pricing where the same rate applies to all card types — Visa, Mastercard, American Express, and contactless wallets — on the standard plan. But the similarities end there.

In-Person Rate: SumUp is Cheaper

On the standard pay-as-you-go rate, SumUp charges 1.69% in person and Square charges 1.75%. That 0.06 percentage point gap is modest — on £10,000 of monthly card sales it amounts to £6 — but it is consistently in SumUp’s favour.

The more significant advantage is SumUp’s Payments Plus plan. At £19/month, it reduces the in-person rate to 0.99% for domestic consumer cards. Square’s Plus plan starts at £29/month but does not reduce the transaction rate — it adds software features. The crossover point: at £3,000/month in card sales, the Payments Plus saving (0.70% x £3,000 = £21) exceeds the £19/month cost. At £5,000/month: SumUp costs £68.50 versus Square’s £87.50.

Online Rate: Square is Cheaper

Square’s online payment rate of 1.4% + 25p for UK cards is significantly lower than SumUp’s 2.50%. For a £50 online sale: Square charges 95p, SumUp charges £1.25. For a £100 online sale: Square charges £1.65, SumUp charges £2.50. Businesses with meaningful online revenue should factor this difference carefully.

Chargeback Fees — A Clear Winner

Square charges £0 for chargebacks. SumUp charges £10 per dispute, non-refundable, deducted whether or not the merchant wins the case. For businesses in sectors prone to disputes — e-commerce, high-value retail, subscriptions — this is a real ongoing cost difference in Square’s favour.

Custom Pricing Threshold

SumUp’s Tailored plan engages at £10,000 per month. Square’s Premium plan begins at £200,000 per year (approximately £16,667 per month). For businesses in the £10,000 to £17,000 per month range, SumUp is the only one of the two that actively offers bespoke negotiation at that volume.

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Hardware

SumUp Hardware

SumUp’s hardware range starts lower: the Solo Lite at £25 is one of the cheapest dedicated card readers in the UK market. The Solo at £79 is a capable standalone reader. The Terminal at £135 includes a built-in printer. The Register at £399 is a dual-screen countertop system. All SumUp hardware comes with a 1-year warranty and a 30-day money-back guarantee. There are no instalment payment plans.

Square Hardware

Square’s hardware starts with the Reader at £19 plus VAT. The Terminal at £149 is standalone with a built-in printer. The Stand at £99 turns an iPad into a countertop POS. The Handheld at £169 includes a built-in barcode scanner. The Register at £699 is a dual-screen countertop system. All Square hardware carries a 2-year warranty and free 30-day returns. Interest-free instalment plans are available from 3 to 12 months on purchases from £29 to £3,000.

Both Offer Tap to Pay

Both SumUp and Square offer Tap to Pay — accepting contactless payments on an existing phone with no hardware required. Both are free to use at the standard in-person rate. This is the lowest-risk way to start accepting card payments with either provider.

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Software & Features

The Biggest Difference: Business Banking vs Commerce Depth

SumUp’s defining software advantage is the Business Account. This is a full UK current account — with an account number, sort code, free business Mastercard, free instant UK transfers, automated expense categorisation, and VAT tracking — built directly into the SumUp platform. Payment receipts land in the account automatically, with next-day payouts guaranteed even on weekends and bank holidays. SumUp’s Business Account is not a prepaid card: it is a fully functional UK current account.

Square does not offer a business bank account in the same sense. The Square Card is a prepaid Mastercard funded from the merchant’s Square balance. It does not provide a dedicated account number or sort code. For businesses that want to consolidate their banking and payments in one place, SumUp’s Business Account is a clear and meaningful advantage.

Square’s defining software advantage is the depth and specificity of its commerce verticals. Square for Restaurants is a purpose-built hospitality management system — table management, kitchen displays, course routing, modifier groups, online ordering, and delivery integration. Square for Retail handles multi-location inventory, variants, stock alerts, and in-store plus online selling. Square Appointments includes a customisable online booking page, SMS reminders, waitlist management, and no-show protection.

Making Tax Digital: SumUp's Unique Advantage

SumUp’s Making Tax Digital integration — developed in partnership with Sage and HMRC-recognised — is a feature Square does not offer. MTD for Income Tax was rolled out in April 2026. Self-employed merchants and small businesses filing quarterly updates to HMRC can do so directly from the SumUp dashboard, removing the need for a separate accounting software subscription.

Clearpay BNPL: Square's Unique Advantage

Square’s Clearpay integration allows customers to pay in four interest-free instalments over six weeks while the merchant receives full payment immediately. The merchant fee is 6% + 30p per transaction — significant, but for higher-value items it can increase conversion rates and average transaction values. SumUp does not offer Buy Now Pay Later.

Developer API

Square’s developer platform is significantly more advanced than SumUp’s. The full Square API covers payments, commerce, customers, staff, and merchants. Terminal API and POS API enable integration with third-party business software. The Square App Marketplace provides hundreds of pre-built integrations. For businesses that need custom payment flows, third-party software connections, or platform-level integration — Square’s API is in a different category.

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Security & Regulation

Both SumUp and Square are FCA authorised electronic money institutions, required to safeguard customer funds in segregated accounts. Neither is a bank. Neither offers FSCS protection. Both use PCI DSS compliant card processing and encrypted payment data. In terms of core regulatory standing, they are equivalent.

Where they differ: Square confirms £0 chargeback fees, active fraud prevention as a built-in product feature, and account takeover protection. SumUp confirms 3D Secure for its Business Account card and biometric login. SumUp charges £10 per chargeback dispute, non-refundable.

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Business Funding

SumUp Cash Advance

SumUp Cash Advance is a commercial merchant cash advance — invite-only for existing SumUp merchants. A fixed fee is charged upfront rather than interest. Funds land in the merchant’s SumUp Business Account within 2 working days. Repayment is automatic as a set percentage of daily card sales, with no deduction on days without sales. Early repayment at no extra charge. SumUp does not publish an APR for the Cash Advance — contact SumUp directly for terms.

Square Loans

Square Loans is a business loan — invite-only, based on Square card sales history, limited to company or corporation structures. A typical offer of £10,000 carries a flat fee of £1,325 (representative APR 18.90% — stated by Square). Repayment is 17.25% of daily Square card sales. Maximum term 18 months. Most merchants repay in 6–9 months. No credit checks, no interest, no late fees. Explicitly not FCA regulated.

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Best For: Side-by-Side

Who Should Choose SumUp?

SumUp is the right choice for UK businesses that:

• Want a free business bank account with a Mastercard, instant UK transfers, and next-day payouts integrated with their payment tools
• Are subject to Making Tax Digital and want compliance built into their financial dashboard — no separate accounting subscription needed
• Process £3,000 or more per month and want to reduce the in-person rate to 0.99% with Payments Plus
• Run a beauty, health, or service business and want appointment bookings, automated reminders, and loyalty tools included
• Want clear FCA regulation, fund safeguarding, and a well-established UK financial services provider
• Need custom pricing at £10,000/month — a lower threshold than Square’s £200,000/year

SumUp may not suit:

• Businesses with heavy online revenue — Square’s 1.4% + 25p online rate is significantly cheaper than SumUp’s 2.50%
• Businesses for whom chargeback fees matter — SumUp’s £10 per dispute adds up in dispute-prone sectors
• Multi-location or enterprise businesses needing a full developer API or advanced integrations
• Businesses wanting Buy Now Pay Later for their customers

Who Should Choose Square?

Square is the right choice for UK businesses that:

• Need the most complete commerce platform — restaurant POS, retail inventory management, appointment booking, online store, and team management from one provider
• Generate meaningful online revenue and want the best online rate — 1.4% + 25p for UK cards
• Want to offer customers Buy Now Pay Later through Clearpay
• Need developer API access or third-party software integrations through the App Marketplace
• Want the best hardware package: 2-year warranty, free 30-day returns, and interest-free instalment plans
• Value £0 chargeback fees — a real saving for businesses in dispute-prone sectors

Square may not suit:

• Businesses that primarily need a full business bank account — Square Card is a prepaid card, not a current account with a sort code
• Businesses affected by Making Tax Digital that want built-in HMRC-recognised compliance software
• High-volume businesses (£3,000+/month) looking specifically to reduce transaction fees — SumUp Payments Plus at 0.99% is a better rate plan
• Mid-sized businesses (£10,000–£16,667/month) seeking custom pricing — SumUp’s Tailored plan is available at a lower threshold

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Verdict

SumUp and Square are both excellent platforms for UK small businesses — and the fact that both are FCA authorised, both transparent about fees, and both backed by genuinely useful free tiers makes this one of the more balanced comparisons in the payment sector.

If your answer includes a business bank account, Making Tax Digital compliance, and the ability to cut your transaction rate to under 1% at volume — SumUp is the right platform. Be aware that SumUp charges £10 per chargeback dispute, which adds up for businesses in dispute-prone sectors.

If your answer includes a full-service restaurant POS, multi-location retail management, a professional appointment booking system, Clearpay BNPL, or a developer API — Square’s breadth of commerce tools is unmatched in this comparison. The 1.75% in-person rate is slightly higher, but £0 chargeback fees, a 2-year hardware warranty, and the depth of the software ecosystem make it the right choice for many growing businesses.

PS: Still comparing options? If Flatpay is also on your shortlist, our full three-way comparison of Flatpay, SumUp, and Square brings all three together. You can also read the dedicated Flatpay vs SumUp and Flatpay vs Square articles if you want to see how Flatpay stacks up against either platform individually.