Square POS vs Zettle vs SumUp: Which Is Best for Your Business?

Choosing the right POS system can feel overwhelming — especially when three of the most popular names all offer sleek apps, affordable hardware, and plenty of features. Square, Zettle by PayPal, and SumUp have become go-to options for small UK businesses, but which one actually delivers the best experience for how you work?

We’ve tested all three in real-world scenarios — from cafés and market stalls to salons and pop-up shops — and in this post, we break down how they stack up on setup, usability, features, pricing, and support.

Setup and Getting Started

Square POS

Square shines in its onboarding experience. You can sign up, get the free POS app, and start taking payments in under 15 minutes. The app is well-designed and intuitive, guiding you through setting up products, taxes, and payment options with ease. The hardware (like the Square Reader) connects quickly via Bluetooth and feels genuinely plug-and-play.

Zettle POS

Zettle’s setup is similarly smooth, especially if you already have a PayPal account. The app is sleek, modern, and easy to navigate. Connecting the Zettle Reader is painless, and we appreciated how clean the initial interface is — ideal for users who want to get started quickly without wading through menus.

SumUp POS Lite / Pro

SumUp takes a slightly different approach. The Lite system offers a preloaded standalone terminal, meaning no app is required. It’s fantastic for countertop retail but offers limited customisation. The POS Pro system (tablet-based) provides far more flexibility — ideal for cafés and hospitality — but setup is more involved, and it works best when ordered as a full kit.

Verdict

Square and Zettle are neck-and-neck for ease of getting started. SumUp Lite is great if you want something instant with zero faff, while SumUp Pro is better suited to those ready for a more advanced setup.

Everyday Use & Interface

Square POS

Square’s interface is arguably the most feature-rich and responsive. Product tiles are customisable, navigation is smooth, and the reporting dashboard is both visual and functional. Whether you’re ringing up items or checking sales history, everything is intuitive.

Zettle POS

Zettle’s user interface is crisp and minimal. It lacks some of Square’s power features, but that simplicity is also its strength. The till layout is fast and user-friendly, and the ability to send digital receipts via SMS or email is built right in.

SumUp POS Lite / Pro

SumUp Lite offers the bare essentials in a clean touchscreen interface — perfect for simple payment acceptance, but it’s limited beyond that. POS Pro, however, delivers an impressive full-featured experience with inventory, modifiers, tipping, and table management. It’s clearly aimed at food and drink businesses, and it shows.

Verdict

Square is best for flexibility and power users. Zettle is smoother for service-based industries. SumUp Lite is perfect for minimalists, and SumUp Pro excels in food-focused retail.

Features and Functionality

Square POS

Zettle POS

SumUp POS Lite/Pro

Lite is limited: basic product buttons and sales history
Pro is robust: staff accounts, tipping, split bills, open tables
Seamless SumUp ecosystem: card readers, online store, invoicing
Optional hardware bundles include receipt printers and cash drawers

Verdict

Square wins on all-round features. Zettle is ideal for those using PayPal or needing quick reports. SumUp Pro is fantastic for hospitality.

Pricing

Square POS

Zettle POS

SumUp POS Lite/Pro

Verdict

SumUp Lite is the cheapest if you’re after a simple solution. Square and Zettle are similar on fees, but Square’s free feature set gives more for your money. SumUp Pro adds a monthly fee, but it’s well worth it for cafés or restaurants.

Support and Reliability

Square POS

Square offers a well-rounded support ecosystem that caters especially well to self-starters and busy traders. Their online help centre is extensive, with step-by-step guides, FAQs, and troubleshooting articles covering everything from hardware setup to advanced integrations. Sellers with active accounts gain access to email and phone support, with phone lines open Monday to Friday during business hours.

In practice, we found response times fast, especially via email. Square also has a lively seller community forum, where business owners share tips and solutions — a valuable resource for newcomers. Reliability-wise, the POS app is solid and rarely crashes, even when multitasking or handling large inventories.

Zettle POS

Zettle’s support system prioritises quick access. Live chat is often available directly within the app or via the website, and agents tend to respond in under five minutes during working hours. Their email support is equally prompt, and their knowledge base is cleanly designed and easy to search.

As a PayPal product, Zettle benefits from PayPal’s established infrastructure — but this also means some users get redirected through multiple departments if issues relate to payments or account verification. That said, the POS software is extremely stable, and we encountered zero crashes or syncing issues during testing.

SumUp POS Lite / Pro

SumUp provides basic support through email and phone, with live chat available for certain users. The team is helpful and professional, but during busy periods we experienced slower response times, sometimes waiting a full business day for a reply.

On the bright side, the POS Lite system is so straightforward that support is rarely needed. The hardware is sturdy, and we encountered no issues with card reading or receipts. POS Pro is more complex and does benefit from better onboarding support. We’d recommend speaking directly to a rep if you’re purchasing the Pro hardware bundle, as they’ll often help you configure your system over the phone or via video call.

Verdict

Square has the best self-service support and documentation. Zettle excels at quick, human-led customer service. SumUp’s support is fine for most users but may lag slightly behind during peak times — though their systems are stable enough that this is rarely a problem.

Final Thoughts: Which Should You Choose?

If you’ve made it this far, you’re clearly serious about choosing the right POS system — and the good news is, all three of these providers offer excellent options. That said, their strengths vary, and the best choice will depend heavily on your industry, setup style, and future plans.

Choose Square POS if you want full control and room to grow.

Square is incredibly versatile. Whether you’re selling art at a weekend market or managing a small retail space, Square’s free tools give you professional-level features from day one. Inventory tracking, sales analytics, customer profiles, invoicing, and even marketing tools are included at no extra cost. You can start with just a phone and a £19 card reader, and add extras like barcode scanners, iPad stands, or loyalty programs as you scale. It’s a modern POS ecosystem that feels both accessible and powerful.

Choose Zettle POS if you want simplicity and PayPal perks.

Zettle is ideal for service-based businesses — mobile hairdressers, wellness practitioners, stylists, and cafés. The interface is elegant and easy to use, and everything works out of the box with minimal setup. Zettle’s reporting tools are clean and helpful, and you can withdraw directly into your PayPal account, often within minutes. It’s a seamless experience that prioritises ease and polish over deep customisation.

Choose SumUp POS if you want plug-and-play or hospitality-grade power.

SumUp Lite is the easiest way to accept card payments without needing your phone — just power it on and go. It’s perfect for counters in small shops or salons. If you run a café, pub, or restaurant and want more control (e.g. table service, tipping, kitchen printing), SumUp POS Pro is a full-featured hospitality solution with tailored tools and clean hardware bundles. It’s one of the few budget-friendly systems that feels purpose-built for hospitality rather than adapted for it.