The 9 best small business payment processing systems in the UK (2025)

Summary

• The best small business payment processing solutions have transparent fees, accept multiple payment options, and integrate with your existing tools.

• Finding the right payment processor lets customers use their preferred payment method, which is key to staying competitive.

• Payment processors offer various payment options, speed up transactions, and open doors to global markets.

• Platforms like Airwallex ‌simplify international business and growth with multi-currency business accounts and seamless integration with other tools.

With more consumers favouring quick payment methods like digital wallets and seamless transactions, small business owners must adapt to stay competitive. In fact, 33% of customers in the UK prefer to pay with digital wallets like Apple Pay, Google Pay, and PayPal.

From traditional credit and debit card processors to innovative fintech options like Airwallex, choosing the right solution can improve customer experience, streamline operations, and drive profitability.

This guide will explore the best small business payment processing options in the UK, highlighting key considerations, emerging trends, and practical tips for making an informed choice.

What is payment processing and how does it work for small businesses?

Payment processing is an online payment system that handles customer transactions, allowing small businesses to accept payments securely and efficiently. It involves moving funds from the customer's account to the business', whether through card payments or digital wallets.

Here’s how the process works:

1. Initiation: The customer submits their payment details via card readers, bank transfer, digital wallet, or mobile app.

2. Payment gateway: A payment gateway securely transmits the payment information to the payment processor.

3. Payment processor: The processor verifies the transaction details with both the customers’ (issuing) and the merchant’s (acquiring) bank.

4. Authorisation: The issuing bank checks the transaction for authenticity and confirms that there are sufficient funds or credit available.

5. Settlement: Once approved, the money from the customer’s account is moved from the customer’s bank to the merchant account.

If you’re ready to consider payment processing services for your small business, take a look at our favourites below that serve a variety of needs.

The key types of payment processors explained

When choosing payment processing for your small business, it helps to understand what’s available. Here’s a list of the main types:

In-person payments are taken in stores using card readers or point-of-sale (POS) terminals, to process chip and PIN, contactless, and mobile payments. Many also offer virtual terminals for taking card payments over the phone. Online checkout processes payments through your website, handling both one-off purchases and recurring subscriptions. These payment gateways integrate with eCommerce platforms and let customers enter their card details securely.

Payment links and invoicing let you create shareable links or digital invoices that customers can pay online in a few clicks. They’re often used by freelancers and service businesses that need flexible payment collection options.

Digital wallets accept mobile payments like Apple Pay, Google Pay, and PayPal, letting customers pay with a tap or click instead of typing card details. They can speed up checkout and reduce cart abandonment.

Cross-border payment processors handle international transactions and multiple currencies, letting you accept payments from customers worldwide in their preferred currency.

Most successful small businesses combine several of the above to give customers maximum flexibility in how they pay.

How payment processing impacts small business cash flow

Unfortunately, two million of Britain’s small businesses fall victim to late payments on average each year. If you’re already low on cash, lengthy payment processing settlement times can create more problems when you need to pay suppliers, staff or settle bills.

When customers pay you through your chosen payment processor, the money doesn't appear in your account immediately. The last stage of the payment process, settlement, takes time.

If you see settlement time noted as ‘T+1’, you should receive the funds one business day after the transaction (Monday sale settles Tuesday), while ‘T+2’ means two business days (Monday settles Wednesday). Most UK payments settle within one to two business days, but can take up to five.

Some processors offer same-day settlement, while others only pay out once a week. Faster settlements may incur a small fee or higher monthly costs, which may be worthwhile if you regularly need immediate access to funds and want to avoid late payment charges or expensive short-term borrowing.

Be sure to consider your day-to-day operations and supplier payment terms when you’re comparing payment processing providers.

The best small business payment processing systems in the UK

We’ve created a list of payment systems for small businesses in the UK to make researching easier for you. See them below.

Read on to compare the key features and costs for these platforms.

1. Airwallex

• Key offerings: global payment acceptance, multi-currency business accounts, FX and transfer solutions, expense management

• Cost: flexible bundled pricing depending on your business needs

Airwallex (that’s us!) is an excellent choice for businesses operating on a global scale. It offers no-code to fully-customised payment integration that simplifies payment processing. It also offers Payment Plugins that work with eCommerce platforms, like Shopify, Magento, and WooCommerce.

It also provides a full suite of services that make handling international transactions easier. For example, Airwallex Payments are integrated with our Global Accounts, which lets you accept payments in multiple currencies from international customers without forced currency conversions. You can then use the same balances to pay international suppliers, saving on unnecessary foreign exchange fees.

2. Adyen

• Key offerings: online payments, POS payments, Adyen for Platforms

• Cost: fixed processing fee of £0.11; payment method fee defined by type of card used

Adyen is a platform that allows small businesses to accept payments1 across various channels – whether online, in-store, or through mobile apps.

Adyen makes payments easier by combining payment processing, gateway, and acquiring into one. This makes it a good choice for businesses that don't want to manage many vendors. While Adyen doesn’t have any set-up fees, each transaction your business accepts will be charged a fee based on the payment method.

Adyen doesn’t offer any integrations to any of the business tools that you may be using. Businesses may benefit from other features that help them manage other parts of their financial operations, like foreign exchange transfers and international payments.

3. Clover

• Key offerings: point of sale (POS) systems, online payments, inventory management

• Cost:

  • £15/month (includes device)

  • Per-transaction pricing, 1.49% on all cards.

Clover is a POS system that offers solutions for accepting payments. These include portable and countertop devices and eCommerce solutions for secure online transactions2.

Clover provides tools for payment processing, inventory management, customer insights, and employee management, all integrated into a single system. While useful, Clover doesn't have the same global reach as Airwallex, and may not be able to scale with your business as it grows.

4. GoCardless

• Key offerings: invoice payments, recurring payments

• Cost:

  • Pay-per-transaction pricing model

  • Price differs depending on the type of plan you select

  • Starts at 1% + £/€0.20 per transaction.

GoCardless is known for its direct debit and recurring payment capabilities 3. GoCardless supports direct debit schemes in multiple countries, allowing businesses to collect payments internationally. GoCardless can also help automate payment collection, making it efficient and reducing the risk of late or missed payments.

GoCardless also integrates seamlessly with popular accounting software. However, it's worth noting that there is an extra fee for higher transaction volumes, and credit card processing isn't available​.

5. Opayo

• Key offerings: card machines, online payments

• Cost: starts at £0/month, from 1.75% transaction fees

Opayo's flexibility, security features, and transparent pricing make it a strong payment processing contender for small businesses 4. The platform has a variety of payment solutions, so you can accept payments online, in-person, or over the phone, making it adaptable to various sales channels. It also supports international currency options.

Opayo is also recognised for its robust security measures. Like many other providers, it includes fraud prevention tools like 3D Secure and tokenisation, providing peace of mind for merchants and customers.

6. Square

• Key offerings: POS system, online payments, invoicing, payroll, banking

• Cost:

  • Packages start at £29+/month

  • Free version available

  • Transaction fees are charged on top of package fees ranging from 1.75% to 2.5% per transaction.

Unlike many payment processors, Square offers a free version, which makes it a cost-effective option for small businesses 5. The platform supports various payment methods, including chip cards, contactless payments like Apple Pay, and online payments, giving businesses flexibility in how they accept money from customers​.

Square features a POS system that allows small businesses to take advantage of inventory management and reporting on top of transactions. In addition to the POS system, Square offers a range of hardware, from mobile card readers to complete register systems. This feature allows businesses to find a solution that best fits their needs.

It’s also easy and quick to set up – great for small businesses seeking a reliable, all-in-one payment solution that can scale as they grow​.

7. Shopify

• Key offerings: online payments, POS options

• Cost:

  • Shopify plans starts at £25/month billed monthly or £19/month billed once yearly on top of pay-per-transaction charges

  • Cost per transaction varies and starts at 25p + 1.5%–-3.1% for credit card rates

  • Cost per transaction for BPNL Klarna is charged at 30p + 4.99%.

Businesses that use the Shopify platform automatically get Shopify Payments, a system that lets businesses accept various payment methods, like credit cards and digital wallets6. Shopify also supports payments in different currencies, which is ideal if you’re looking to sell internationally. Businesses also have the flexibility of choosing from different plans, as well as monthly and annual billing options.

Airwallex’s Payment Plugin also integrates with Shopify, allowing you to collect payments from your Shopify sales. It’s integrated with Airwallex’s Business Account, which can help reduce the impact of exchange rate fluctuations and FX fees with like-for-like settlement.

8. Stripe

• Key offerings: online payments, in-person payments, payments for platforms, issuing, revenue automation

• Cost:

  • 1.5% + 20p for standard UK cards

  • 2.5% + 20p for EU cards

  • 3.25% + 20p for international cards (+2% if currency conversion is required).

Stripe is an eCommerce payment system that offers global payments in over 135 currencies. Stripe has comprehensive security and rigorous compliance, tools to build out custom checkout flows, a robust developer platform, and third-party integrations. It’s also recognised as one of the leading PCI-compliant payment gateways globally7. Unlike Airwallex, it doesn’t offer FX and Transfers or spend management solutions.

9. Zettle by PayPal

• Key offerings: Payments, POS systems, inventory management

• Cost:

  • Charge per transaction by payment type

  • 1.75% per transaction for major cards and mobile wallets.

Zettle by PayPal offers payment solutions and POS systems best suited for brick-and-mortar stores like food trucks, pop-up shops, or market stalls8. Zettle’s no startup costs make it an attractive option for small businesses. Zettle charges per transaction and offers a custom rate plan for businesses with larger transactions.

While Zettle offers multiple physical payment options, Airwallex has a stronger focus on accepting online payments, with comprehensive multi-currency support and competitive foreign exchange rates for international transactions.

How to set up payment processing for small businesses in four steps

After identifying your needs, choose a payment processor that integrates with your existing systems with minimal friction. Once you’ve created an account with the payment processor, here are some steps to help you get started:

1. Register for a merchant account: Some payment processors require you to have a merchant account to process credit card payments. If your processor requires one, your bank or processor can help set it up.

2. Integrate the processor into your website: Most payment processors provide plugins or APIs for integration. If you’re using popular eCommerce platforms, you may already have a ready-made integration. If you’re looking for a more customised solution, you may need to hire a developer. Airwallex has no code and prebuilt solutions, and developer tools to suit any business.

3. Configure your payment settings: Choose and enable different currencies and payment methods depending on what you wish to offer your shoppers.

4. Test your payment system: Before launching, run a few test transactions to check if everything, including payment methods, security features, and the checkout flow, is functioning correctly.

5. Launch your payment systems: Once you’ve tested your payment system thoroughly, you can start accepting payments.

How to choose the best payment processing service for your small business

When choosing a payment processing service for your small business, you’ll want to take a look at several factors to help you select the best option. Here are some main things to consider:

• Services provided: Different payment processors offer different services, from basic transaction processing to additional features like invoicing, recurring billing, and fraud protection. Consider the services that align with your business needs.

• Costs and fees: Most platforms charge transaction fees, which often vary depending on the payment method. Before choosing a payment processor, consider all fees involved and whether they fit into your budget. This includes setup fees, equipment charges, and monthly fees.

• Customer preferences: Consider your customers' preferences. If you find that most of your customers like to use Apple Pay, consider a payment processor that supports those types of payments.

• Integrations available: Having a payment processor that integrates with your existing tools is key. Seamless integration can save you time and prevent operational headaches. For example, Airwallex integrates with popular accounting tools such as Xero, Quickbooks, and NetSuite.

• Ease of use: The payment processor needs to be easy to set up and use. It should also be intuitive for your customers to use.. Be sure to research and look at reviews of your potential payment processor to see what customers are saying about it.

Considering these factors will help you choose a payment processing service that supports your business goals and provides a smooth payment experience for your customers.

Common mistakes small businesses make with payment processing

Even well-intentioned small business owners can make costly errors when setting up payment processing. Here are the most frequent mistakes (and how to avoid them).

Choosing the wrong fee structure. Processors offer different pricing models that suit different business types. For example, subscription pricing (like £20/month + 0.99%) may work better for high-volume businesses, while pay-as-you-go (1.75% per transaction) could suit businesses with fewer sales.

Choosing the wrong settlement timeline. Cash flow problems often stem from not understanding when funds will be available. Standard settlement is around two to five business days, but some processors offer next-day or even same-day transfers. Factor in your working capital needs when comparing options.

Ignoring international payment capabilities. Even if you only serve UK customers now, international opportunities often arise unexpectedly through online sales, supplier changes or business expansion. Switching processors is disruptive, and some providers charge premium rates (3%+) for international cards. Consider a processor that handles global payments efficiently from day one, even if you don't need it yet.

Overlooking customer support quality. Payment issues don't always align with business hours, and weekend outages or evening transaction failures can cost sales. Check if your provider’s support includes a dedicated account manager, technical help or just account queries – there's a big difference.

Not integrating with existing systems. Manual reconciliation is tedious and error-prone. Without automatic sync to Xero or QuickBooks, you'll spend hours tracking and approving payments, and risk missing disputed transactions.

Accept payments anytime, anywhere

Finding a payment processor that fits your small business’ goals can help you expand your customer reach globally and make it convenient for your customers to pay.

With Airwallex, small businesses can accept payments in over 180 countries and can process payments with major card schemes, like Visa, Mastercard, and Amex, and over 160 payment methods. Plus, businesses can benefit from competitive foreign exchange rates (0.5–1% above interbank), flexible integration options, and spend management tools.

Airwallex is regulated in all markets it operates in, with 60+ licences and permits globally. Join the 100,000 businesses that trust us to process over US$100 billion in global payments volume annually.

Frequently asked questions

Below are some frequently asked questions related to small business payment processing:

What are the benefits of payment processing for UK small businesses?

The benefits of payment processors for small businesses include accepting global payments easily, expanding their customer base, and streamlining operations.

Also, many providers offer plug-and-play solutions that are simple to set up, even without dedicated IT staff. Some also integrate with tools like Xero and QuickBooks, saving time on accounting and business management.

Payment processors vs. payment services providers (PSP): what’s the difference?

Payment processors help facilitate financial transactions between merchants and customers securely. A payment processor is an intermediary and only handles a specific step in the larger payment processing workflow.

Payment service providers (PSPs), on the other hand, are third-party companies that help businesses accept electronic payments. Beyond payment processing, PSPs also offer payment gateways, fraud prevention, and reporting and analytics.

Disclaimer text: We wrote this article in Q2 2025. We based the information on our own online research and were not able to manually test each tool or provider. The information is provided for educational purposes only, and a reader should consider the specific requirements of their business when evaluating providers. This research is reviewed every six months. If you would like to request an update, feel free to contact us at [email protected].

Sources:

1. https://www.adyen.com/pricing

2. https://uk.clover.com/start-taking-payments/

3. https://gocardless.com/pricing/

4. https://www.elavon.co.uk/

5. https://squareup.com/gb/en/pricing

6. https://www.shopify.com/uk/pricing

7. https://stripe.com/gb/pricing

8. https://www.zettle.com/gb/pricing