It’s easier than ever to accept credit and debit cards. Forget the costly card machines of yore. Instead, check out these contactless card readers that process payments with a smartphone or tablet through easy-to-use, free point of sale (POS) apps.

The race between the most popular mobile card readers in the UK is close. On our top three list, cost-conscious start-ups often prefer SumUp’s lowest transaction fee. Zettle’s card reader is simply the most loved while Square has the most superior free card reader app.

If that isn’t enough, all of these companies now offer standalone, portable touchscreen terminals that work without a phone.

Zettle Reader 2 SumUp Air Square Reader
iZettle Reader 2Full review SumUp Air smallFull review Square ReaderFull review
Solution Card reader + smartphone/tablet app
Price £29 + VAT (offer) £39 + VAT (offer) £19 + VAT (offer)
Transaction fee 1.75% 1.69% 1.75%
Contract lock-in None None None
Monthly fee None None None
Minimum sales volume None None None
Cards accepted   Visa Visa Electron V Pay Mastercard Maestro American Express Union PayDiners ClubJCBDiscover   Visa Visa Electron V Pay Mastercard Maestro American ExpressUnion PayDiners ClubDiscover  Visa Visa ElectronV PayMastercard Maestro American Express
Contactless ContactlessApple PayGoogle PaySamsung Pay ContactlessApple PayGoogle Pay ContactlessApple PayGoogle PaySamsung Pay
Payouts 1-3 working days 1-3 working days 0-2 working days
PIN pad On card reader On card reader In app on mobile screen
Compatible receipt printers Star Micronics, AirPrint Star Micronics, Bixolon, AirPrint, Google Cloud Print Star Micronics, Epson
Digital receipts
Staff accounts
Product library
Tipping
Sales reports CSV, Excel, PDF, Xero & QuickBooks integration CSV, Excel, PDF, SumUp Accounting CSV, Xero, Zoho Books & several other integrations
Use abroad
Zettle SumUp Square logo
Zettle
Reader
SumUp
Air
Square
Reader
iZettle Reader 2Full review SumUp Air smallFull review Square ReaderFull review
Card reader + smartphone/tablet app
£29 + VAT (offer) £39 + VAT (offer) £19 + VAT (offer)
1.75% transaction fee 1.69% transaction fee 1.75% transaction fee
No contract lock-in
No monthly fees
No minimum monthly sales volume required
  Visa Visa Electron V Pay Mastercard Maestro American Express Union PayDiners ClubJCBDiscover   Visa Visa Electron V Pay Mastercard Maestro American ExpressUnion PayDiners ClubDiscover  Visa Visa ElectronV PayMastercard Maestro American Express
ContactlessApple PayGoogle PaySamsung Pay ContactlessApple PayGoogle Pay ContactlessApple PayGoogle PaySamsung Pay
Payouts 1-3 working days Payouts 1-3 working days Payouts 0-2 working days
With physical PIN pad With physical PIN pad PIN pad in app on mobile screen
Compatible receipt printers
Star Micronics, AirPrint Star Micronics, Bixolon, AirPrint, Google Cloud Print Star Micronics, Epson
Digital receipts
Staff accounts
Product library
Tipping feature
Sales reports
CSV, Excel, PDF, Xero & QuickBooks integration CSV, Excel, PDF, SumUp Accounting CSV, Xero, Zoho Books & several other integrations
Use abroad?
Zettle SumUp Square logo

The three systems share characteristics that make them very attractive to small businesses. Setup costs are very low, and there are no fixed, monthly fees and no minimum transaction volume required. Plus: there’s no contractual commitment with any of these companies.

SumUp, Zettle and Square are therefore suitable both for infrequent use and processing many transactions daily as your primary POS solution.

Photo: SumUp

With SumUp Air and its app, you can accept almost any payment method.

Cards, payouts and charges

As opposed to a traditional card reader machine with a contract, you purchase the mobile card readers for a low price with no rental charges or lock-in.

Zettle currently accepts the most payment cards. On top of Visa, Mastercard and American Express accepted by all three, Zettle can handle Diners Club, JCB, Discover and UnionPay. SumUp also accepts Diners Club, Discover and UnionPay, but not JCB.

Zettle and Square charge a fixed percentage (1.75%) for all chip and contactless card transactions, but SumUp offers the lowest card rate at a fixed 1.69%, beating Zettle and Square by 0.06 percentage points. All of these fees apply to any credit and debit cards, including foreign-issued and premium brands like Amex.

Zettle SumUp Square
Card readers From £29* From £39* From £19*
Best deal
Chip, tap payments 1.75% 1.69% 1.75%
Online store payments n/a 2.5% 1.4% + 25p–2.5% + 25p
QR code payments 1.75% (via PayPal) 2.5% 1.4% + 25p–2.5% + 25p
Payment links 2.5% 2.5% 1.4% + 25p–2.5% + 25p
Invoice transactions 2.5% 2.5% 2.5%
Keyed transactions n/a 2.95% + 25p 2.5%
Monthly fee None None None
Min. sales volume None None None
Settlement Free Free Free, 1% for instant

*Excluding VAT. Offers apply to the first card reader purchased.

Zettle SumUp Square logo
Card readers from £29* (offer) Card readers from £39* (offer) Card readers from £19* (offer)
Chip, tap payments
1.75% 1.69% 1.75%
Remote transaction fee
Links, invoice:
2.5%
QR code:
1.75% (via PayPal)
Links, invoice, online store:
2.5%
Virtual terminal, keyed:
2.95% + 25p
Links, online store:
European cards:
1.4% + 25p
Intl. cards:
2.5% + 25p
Virtual terminal, keyed, invoice:
2.5%
Monthly fees
None None None
Minimum sales volume required
None None None
Payouts
Free Free Free, 1% for instant
Zettle SumUp Square logo

*Excluding VAT. Offers apply to the first card reader purchased.

With SumUp, settlement takes up to three working days. Zettle and Square will deposit funds in your bank account slightly faster, within one or two working days.

In addition, Square offers Instant Transfers, a voluntary setting that clears transactions in your bank account within 20 minutes at an additional cost of 1% per transaction. To compete, SumUp Business Account (with prepaid Mastercard) gives you access to transactions within 24 hours, even on weekends – and for free.

Point of sale features

All three card readers work with iPad, iPhone and Android tablets or phones, provided the associated payment app is downloaded and connected over Bluetooth.

The inventory libraries in each app look neat with images and product information so you can sell different sizes and types of each item. Square’s app, called Point of Sale, beats Zettle and SumUp with additional features like split bills, custom employee permissions (costing extra) and much more.

Photo: Square

Square Point of Sale

Square has the best point of sale software connecting with its credit card reader.

Zettle’s POS features come at a close second, with physical gift card options, stock counts, barcode scanning via the phone camera, and more. The SumUp app has slightly fewer POS features, but more remote payment methods.

It is possible to use any of the card readers with more complex POS software so you are not limited to the free apps.

Square users can subscribe to Square for Retail, Square for Restaurants or Square Appointments for advanced till features, or a few excellent till systems like Vend and TouchBistro.

Zettle’s only upgrade is the Food & Drink app for small cafés, food trucks or similar, but Zettle Reader is compatible with many leading POS systems.

SumUp merchants can upgrade to SumUp Point of Sale, a user-friendly POS system where you can add modules of specialised features to suit any type of business.

What are the alternatives? See all app-based card readers in the UK

Standalone terminals available

If card readers for phones are not for you, Square, Zettle and SumUp offer card terminals that work independently. These have exactly the same transaction fees, no monthly costs and no contractual commitment.

One is Square Terminal, which has a touchscreen with POS features similar to the Square Point of Sale app. It works with secured WiFi connections only, so is best at a confined location, but can be carried around for table-service around your premises. It also has a built-in receipt printer.

Zettle SumUp Square
Card reader with app
Zettle Reader 2:
£29*
SumUp Air:
£39*
Square Reader:
£19*
Standalone card machine
Zettle Terminal:
£149*
SumUp Solo:
£79*
SumUp 3G & Printer:
£129*
Square Terminal:
£149*

*Excluding VAT. Free shipping included.

Zettle SumUp Square
Card reader with app
Zettle Reader 2:
£29*
SumUp Air:
£39*
Square Reader:
£19*
Standalone card machine
Zettle Terminal:
£149*
SumUp Solo:
£79*
SumUp 3G & Printer:
£129*
Square Terminal:
£149*

*Excluding VAT. Free shipping included.

SumUp Solo, on the other hand, doesn’t just work with WiFi – it also works with GPRS, EDGE and 3G through its inbuilt SIM card that comes with unlimited free data. It has very simple features – basically, it just accepts cards or mobile wallets and refunds payments. Alternatively, the standalone terminal SumUp 3G and Printer can print receipts too.

Zettle Terminal is a new entry that comes with the Zettle POS app built in and looks a lot like a smartphone. It works directly with WiFi, 3G or 4G (SIM card with unlimited data is included). It can be purchased on its own or with a receipt printer dock.

Photo: Zettle by PayPal

Zettle Terminal, Reader and POS app

Zettle Terminal and Zettle Reader with the POS app.

Free online payment tools included

Square users get most options for keyed and online payments: a free virtual terminal for telephone payments, e-gift cards, digital invoices (with invoice app), online store builder, payment links, QR codes for touch-free payments, and the ability to manually enter card details in the POS app.

Remote payment Zettle SumUp Square
Payment link
QR code
E-gift card
Email invoice
Telephone payment
Online store
Click & collect
Zettle SumUp Square
Payment links
QR codes
E-gift cards
Email invoices
Telephone payments
Online store
Click & collect

In second place, SumUp has complimentary payment links to share via QR code, social apps or text, digital gift cards, email invoices and a basic online store created through the app in a few simple steps. A basic virtual terminal can also be activated for most users, including manual card entry at the POS checkout.

Zettle only offers basic email invoicing, gift cards, payment links and QR code payments via PayPal, so remote payment options are a bit limited. You can nevertheless integrate the account with ecommerce platforms like Shopify and PrestaShop.

Many of these online payments were introduced as a response to the Covid-19 pandemic, and they are definitely handy for remote or socially distanced payments and online orders, but only Square and SumUp support a click-and-collect service.

They’re complete business solutions

Square, Zettle and SumUp are not just about card readers. Common to them all is their broad offering of integrated business tools connected to the same account, so you can get more done with less effort.

All of them have inventory management features for both retail and hospitality, the most advanced coming from Square.

Analytics and sales reports are included by all, with options to export data – or in the case of Square and Zettle, integrate with accounting software like Xero and QuickBooks. SumUp cannot integrate with accounting software, but is currently rolling out its own SumUp Accounting system to merchants.

Square is constantly expanding its own (paid or free) business tools, such as the new email marketing and customer loyalty features built into the platform. Users can also connect with lots of external software for things like ecommerce, marketing, food delivery and inventory management.

Zettle only connects with a few accounting systems and ecommerce builders. SumUp has a closed system relying on its own features instead of integrations.

No matter which platform you choose, you benefit from a lack of contract obligations, monthly fees or complicated terms. Instead, you get simple fees and a trusted payment system designed to help your business grow – it doesn’t get simpler than that.