Invoice apps are gaining ground in the UK, but which are genuinely trusted by small businesses? The short answer: not many. There’s no shortage of invoicing tools out there, but they vary hugely in costs and features.

Many companies offer an invoicing app as an added extra to a main product. They can be grouped into:

  • Invoicing in accounting software
  • Invoicing from payment company
  • Invoicing from digital bank

Some allow you to receive payments directly through the invoice through a link, others are not integrated with a payment system. For instance, certain apps just have free invoice templates where you can include your bank details for a manual bank transfer.

We’ve tested different invoicing apps and shortlisted what we think are the best options.

Best invoice apps for a small business in the UK:

Invoice app Per month Transaction fees Website
Square £0-£20* Card:
6% + 30p
Revolut From £0 Card:
1%-2.8% + 20p
Bank transfer:
1% + 20p (max. £1)
SumUp £0-£7* Card:
2.5% (Free plan) / 1.25% (Pro plan)
Intuit QuickBooks £10-£70* Bank transfer:
1%-2% + 20p (max. £4)
1.45%-2.9% + 30p
Zoho Free Via third party
Monzo £5 Card:
1.5%-3.25% + 20p
Bank transfer:
Invoice2go £4.17-£29.99* Card:
1.9%-3.9% + 20p
2.9% + 30p
Xero £15-£55* Card:
1.5%-3.25% + 20p
Bank transfer:
From 1% + 20p
PayPal Free Card:
From 2.9% + 30p

*Excluding VAT.

Invoice app Per
Square £0-£20* Card:
6% + 30p
Revolut From £0 Card:
1%-2.8% + 20p
Bank transfer:
1% + 20p (max. £1)
SumUp £0-£7* Card:
2.5% (Free plan) / 1.25% (Pro plan)
Intuit QuickBooks £10-£70* Bank transfer:
1%-2% + 20p (max. £4)
1.45%-2.9% + 30p
Zoho Free Via third party
£5 Card:
1.5%-3.25% + 20p
Bank transfer:
Invoice2go £4.17-£29.99* Card:
1.9%-3.9% + 20p
2.9% + 30p
Xero £15-£55* Card:
1.5%-3.25% + 20p
Bank transfer:
From 1% + 20p
PayPal Free Card:
From 2.9% + 30p

*Excluding VAT.

What to look for in invoicing apps

Like most life admin today, invoicing is usually done online, typically via email. Many sole traders and small businesses also like to send invoices from a mobile app, which is what we are looking at in this article. So what should you consider when choosing an invoice app for billing clients?

First of all, all invoicing solutions should as a minimum comply with GOV.UK’s invoice requirements by including certain information like a unique invoice number, customer address, payment due date and a list of products charged for.

You should also consider the features that help you get paid promptly and make your business look more professional:

  • Card payment acceptance: Bank transfers may be cheaper, but offering card payments via a digital invoice reduces payment time – a big benefit for cash flow.
  • Payment reminders: One of the most effective ways to prevent non-payment is to send payment reminders, and many invoicing apps automate this.
  • Invoice customisations: Adding a company logo, colour scheme, fonts and design allows you to match your brand with the invoice, but not all apps can do it.
  • Terms and conditions: Some businesses have custom terms and conditions for their services, so it’s worth checking if you can attach files or edit a T&C template.

Other questions to consider is whether the invoice software should integrate with accounting or a specific payment system.

Square – best features in a dedicated app

Our rating
  • Free or paid plan, no contract

  • Integrated card processing at flat rate

  • Next-day deposits in bank account

  • Lots of additional payment tools

We think Square Invoices is the best free invoice app in the UK. It’s easy to use, and you can accept card payments directly through the invoice for 2.5% per card transaction or 6% + 30p per Clearpay transaction (buy now, pay later).

“I’ve always had a positive experience when testing Square Invoices. The app is regularly updated, easy to use and with an impressive amount of features. It’s the best free invoice app, in my opinion.”

– Emily Sorensen, Senior Editor, MobileTransaction

It’s free to use the basic app features, including unlimited invoices – you only pay when the client pays online through the link in the email invoice. The paid Plus subscription has more advanced features, like custom layouts and organising project files into folders.

Image: MobileTransaction

Square Invoices app menu and invoice preview

Square Invoices has more features than other free invoicing apps.

Payments are deposited in your bank account the next working day, or sooner if you opt for Instant Transfers (for an extra 1% fee). When signing up through the simple online form, Square performs identification checks to verify your business and bank account.

It can take up to 4 working days before the bank account is linked to your Square account, but it’s possible to accept invoice payments sooner, in which case the money is pending in the Square account.

On the paid plan, the app allows you to send estimates converting into invoices when the client accepts the quote. You can also set up recurring invoices, invoice tracking and deposit requests. If the client does not pay directly through the invoice link, you can mark invoices as paid with cash, gift cards, Bacs or another method.


Monthly cost: £0 (Free plan), or £20 + VAT (Plus plan)

Card processing: 2.5% transaction fee

Instant Transfers: Additional 1% of transaction amount

Existing users of Square Reader can already send invoices through the Square Point of Sale app for the same fee. If you have the Square Reader, you can even accept invoice payments directly through the invoice app, if the card is physically processed in the card reader, for the lower fee of 1.75%.

Integrated payments: Square (Visa, Mastercard, Maestro, American Express), Clearpay

Best for: Most accessible solution to receiving invoice payments in your bank account.

Revolut – just enough advantages to make it great

Our rating
  • Free or paid plan, no contract

  • Integrated card processing

  • Next-day deposits in Revolut account

  • Good multi-currency options

Revolut offers a feature-rich business current account (not bank account) ideal for merchants that charge across borders. Email invoices can be generated and managed in the Revolut Business app on both the free and paid business account plans.

Image: MobileTransaction

Revolut invoice app and payment screen

Revolut lets you send invoices to pay via card, bank transfer, mobile wallet or Revolut Pay.

The invoicing feature is accessed via a “Request money” button in the Business app dashboard on your iPhone or Android smartphone. The menu gives you a choice between sending a payment link, generating a QR code, creating a payment page to share online, or sending an email invoice.

When you choose ‘invoice’, a user-friendly screen lets you create one. You can add a customer (new or saved), message for the email, currency (28 to pick from), item(s) and costs, and an invoice note. Invoices can recur on a schedule or be sent as a one-off, with or without automatic reminders to pay.

We really like the fact you have full control over which payment methods the customer can use. This includes card payments (Visa, Mastercard, Apple Pay, Google Pay), Revolut Pay (from other Revolut accounts), and ordinary or streamlined bank transfers where the payer doesn’t need to manually enter account details.


Monthly cost: £0-£100 for business account

UK consumer cards, bank transfers, Revolut Pay: 1% + 20p per transaction

All business and non-UK cards: 2.8% + 20p per transaction

The easy bank transfer option lets the payer pick their bank from a list and verify the payment via their banking app, which is simpler than manually entering account details.

“I found it fast and easy to create Revolut invoices and accepting payments through them. It’s big plus for me that the invoices include both card payment and streamlined bank transfer options to maximise the chance of a fast payment.”

– Emily Sorensen, Senior Editor, MobileTransaction

Transaction fees are low for domestic consumer cards and bank transfers, while all other cards cost more. The fact you can opt for a free Business account plan makes Revolut great value, particularly if you need a multi-currency business account to save money on cross-border transfers.

Just beware that all of the payment features are only available with a Merchant Account requiring a separate application after getting the Business Account. Once approved, you receive payouts the next day in the Revolut account.

Integrated payments: Visa, Mastercard, Apple Pay, Google Pay, Revolut Pay, bank transfer

Best for: Revolut Business account users whose clients like a choice between card and bank payments.

SumUp – better than average for a free solution

Our rating
  • From £0/month, no contract

  • SumUp processes the card payment

  • Payouts in 1-3 working days

  • POS and remote payment features

SumUp is best known for their cheap card readers and payment features for small businesses. But the platform has added a wealth of new features to help merchants receive payments remotely, including digital invoicing.

SumUp Invoices can be created, sent and managed from SumUp App.

SumUp has no contract terms, and there’s no monthly fee for standard-template invoicing, just a pay-as-you-go rate of 2.5% per card transaction. Upgrading to the Pro plan gives you invoice customisations, bank transfers to any bank account, and 14 invoice languages. Crucially, the transaction rate drops to 1.25% for all cards on Pro.

It’s easy to get started: just sign up on the website, connect your bank account and start invoicing clients from the SumUp App or browser dashboard.

SumUp App is actually a payment and simple point of sale (POS) app. It has a product library, transactions overview and checkout interface for accepting cards, cash, QR code payments, keyed transactions and payment links.

In another section of the app, you can create, manage and monitor invoices and quotations with your own terms and conditions attached.


Monthly fee: £0 (Free plan) or £7 + VAT/month (Pro plan)

Transaction fee: 2.5% (Free plan), 1.25% (Pro plan)

There is no limit on how many email invoices you can send, and items from your library of products and customers can be added. If you log into your SumUp account on a computer, you can create credit notes and delivery notes as well, neither of which are available in the app.

“Apart from the very user-friendly invoice management in SumUp App, I was struck by how professional the extra invoicing features in the browser dashboard are.”

– Emily Sorensen, Senior Editor, MobileTransaction

Payouts take 1-3 working days to reach your bank account. With the free SumUp Business Account and Card (online account and prepaid debit card), you can receive transactions the next day, including on weekends.

Integrated payments: SumUp (Visa, Mastercard, Maestro, American Express, Diners Club, Discover, JCB)

Best for: Selection of free payment methods, not just invoices, from the same app.

QuickBooks – best with accounting software

Intuit QuickBooks
Our rating
  • From £10 + VAT/mo

  • Trusted accounting provider

  • Great support for HMRC filing

  • Multi-currency support

Mostly known for accounting software, Intuit QuickBooks’s invoicing is an integral part of their offering too. All the tiered QuickBooks packages include a variety of business tools, so this is a good choice for managing your books and invoices in one place.

QuickBooks Invoice app

The QuickBooks invoice app gives an intuitive overview of paid and outstanding payments.

If you’re already using QuickBooks for bookkeeping, you might as well use the invoicing features, included to some extent on all plans. The less dispersed your documents, invoices and receipts are, the more streamlined your admin can be. A plus is that QuickBooks is HMRC-recognised and adheres to the government-incentive Making Tax Digital.

The app is compatible with iPhone, iPad and Android phones and tablets.

The number of invoicing features depends on your plan. The cheapest subscription, called Self-Employed (£10 + VAT/month), is for sole traders who are not VAT-registered. It includes unlimited invoices by email and the ability to track which ones have been read.

The next tier, Simple Start (£14 + VAT/month) is for sole traders and companies, whether VAT-registered or not. This plan has more customisation tools, payment tracking, recurring invoices and the ability to accept invoice payments online.


Monthly fee: £10 + VAT/mo for Self-Employed, £14 + VAT/mo for Simple Start

GoCardless bank transfer: From 1% + 20p for (domestic) and 2% + 20p (international)

PayPal payments: From 1.45% + 30p for Visa and Mastercard, 3.5% for Amex, 2.9% + 30p for PayPal Wallet

Higher plans do not include more invoicing functions, only more accounting tools.

You can either accept payments outside the QuickBooks system and mark when invoices are paid, or accept payments through a link on the electronic invoice (except on the Self-Employed plan).

The latter can be done as a GoCardless Direct Debit integration which has no setup fee or monthly costs, just a transaction fee from 1% + 20p. PayPal can be integrated too – but again, only on Simple Start and higher plans.

Integrated payments: PayPal (Visa, Mastercard, American Express), GoCardless Direct Debit

Best for: SMEs wanting a complete, HMRC-compliant invoicing and accounting system.

Zoho – “forever free” invoice app with many features

Our rating
  • No monthly fee or contract

  • No sign-up for free invoice generator

  • Good choice of payment integrations

  • Many features on all plans

Zoho is another all-round accounting system, but their invoice app is totally free with no contract, tiered plans or surprise add-ons. You get detailed invoicing features without a paid subscription.

If you only want to create a PDF invoice to download or send from your phone, you can also do that free without creating a login or signing up for anything in the Zoho Invoice Generator app (separate from the main Zoho Invoice app).

Zoho Invoice app

Zoho Invoice is compatible with macOS, iOS, Android and Windows phones and tablets.

The invoicing apps are supported on macOS, iOS, Android and Windows mobile devices. To be clear: the Invoice Generator app is a separate app you can download and use for free. What we describe below requires the free Zoho Invoice app, which has more in-depth features.

Features include recurring invoices, estimates, retainers, expense tracking, time tracking, multi-currency features, digital signatures, automated workflows, integrations with external apps, and much more.

The Zoho Invoice app lets you create up to 1000 per year, adapted to comply with your local tax laws, language and currency.


Monthly cost: None

Transaction fees: Via payment processor (PayPal, Stripe, etc.)

Zoho can integrate with a number of payment services, so you can accept payments through the invoice rather than outside the platform. Transaction fees depend on the chosen payment system.

Integrated payments: Braintree, CSG Forte, GoCardless, PayPal, Square, Stripe, Verifone

Best for: Cheap way to start small, with options to expand features later on.

Monzo – free account-to-account payments

Our rating
  • Requires £5/mo Pro plan

  • Uses Stripe for card payments

  • Payouts within 2 working days

  • With full-fledged bank account

The online bank Monzo offers a decent business account that can be used for free (Lite plan). If you need invoicing, you can subscribe to its Pro plan for £5 monthly with no contractual obligation. This adds features like accounting integration, multi-user access, tax pots and digital invoicing.

Image: Monzo

Monzo invoice app and desktop list

Monzo Bank offers an in-app invoicing solution with a streamlined bank payment option.

Once subscribed, you can generate invoices in the Monzo Business app on your smartphone. Customisation options include products or services paid for, your own logo and a note on each invoice.

Invoices are generated in a PDF format and sent via email, text or messaging app on your phone.

To accept card payments, you have to register with Stripe and connect that with Monzo. This is easily done via the Monzo app. It means transactions are processed via Stripe, so you are charged Stripe’s processing fees.

The biggest advantage of Monzo invoicing is its new integration with “easy bank transfers”, enabling customers to pay via bank transfer in a few taps on their phone. It involves selecting their bank from a drop-down menu and verifying the transaction in their banking app. These payments are free to accept for the rest of 2024.


Monthly fee: £5/mo for Business Pro

Card transaction fee: 1.5% + 20p (UK consumer cards), 1.9% + 20p (UK premium cards), 2.5% + 20p (EEA cards), 3.25% + 20p (all other cards)

‘Easy’ bank transfers: Free until year 2025

Card payments via Stripe cost between 1.5% + 20p and 3.25% + 20p, depending on the type of debit and credit card. Funds arrive in your Monzo bank account within a few working days, or faster via bank transfer.

Integrated payments: Stripe (Visa, Mastercard, Amex, Google Pay, Apple Pay), bank transfer

Best for: Monzo Business account holders who want the cheapest, easy way to accept bank transfers.

Invoice2go – established invoicing brand

Our rating
  • From £4.17/mo

  • Annual or monthly billing

  • Settlement takes 2-5 working days

  • Features are better on pricier plans

Invoice2go is a well-known invoice app in the UK, which is understandable given its sleek looks and branding, but it does not offer a free app (barring the 30-day trial). It comes with invoice templates, invoice tracking, multi-currency support, customisation, recurrent billing and estimate-to-invoice conversion.

Invoice2go app invoice

The invoice templates in Invoice2go have several customisation options.

Invoice2go has three plans that can be paid upfront monthly or annually (the latter works out cheapest per month). The cheapest subscription, Starter, includes 30 invoices for the whole year on an annual plan (£4.17/month) or 2 invoices per month on the monthly plan (£4.99/month).

The annual Professional plan costs £6.67/month and includes 100 invoices annually. The same plan paid monthly (£7.99/month) allows for 5 invoices per month.

Premium (£29.99/month on a monthly plan, £25/month on annual) allows unlimited invoices to be sent.

All the subscriptions allow you to have unlimited clients, team members and projects, and send unlimited estimates. The system integrates with Stripe for card transactions that take around 3-5 working days to reach your bank account (or up to 7 working days in some cases – quite slow!).

The higher your plan, the lower is your transaction fee through Stripe.


Monthly fee: £4.17-£25/month for annual plans, £4.99-£29.99/month for monthly plans

Card payments: 1.9%-2.4% + 20p for domestic cards and Amex, 3.4%-3.9% + 20p for foreign cards

PayPal transactions: 2.9% + 30p

PayPal is also integrated for a fixed fee of 2.9% + 30p per transaction regardless of the plan, though PayPal tends to add more fees to that.

On the plus side, Invoice2go specialises in invoicing features rather than the general accounting tools that QuickBooks and Xero, for example, offer together with invoicing. However, many users have reported the app is cumbersome to use, the disappearing of features or data saved in the app, and generally the high price for an increasingly problematic user experience.

Integrated payments: PayPal (Visa, Mastercard, American Express)

Best for: Those who don’t mind paying more for a reputable, dedicated invoice app.

Xero – trusted by bigger businesses

Our rating
  • From £15 + VAT/mo

  • Optional business add-ons

  • Connects with Stripe and GoCardless

  • Integrates with Xero accounting

Better known for its advanced bookkeeping software, Xero’s invoicing app (actually the main Xero Accounting app) is approachable for small businesses too.

The app works on iPhone and Android devices, but it’s quite expensive because the plans include accounting functions too. You can’t just pay for invoicing for a lower fee.

Xero invoice app screens

The main Xero Accounting app doubles as an invoicing app.

The cheapest plan, Starter (£15 + VAT/month), lets you send quotes and up to 20 invoices per month from the app, and enter 5 bills monthly. The higher plans, Standard (£30 + VAT/month), Premium (£42 + VAT/month) and Ultimate (£55 + VAT/month), provide unlimited invoices, quotes and bills.

Regardless of the plan, you get accounting reports, Construction Industry Scheme (CIS) calculations, VAT returns to the HMRC, and Hubdoc capture of receipts. The Standard plan lets you reconcile transactions in bulk, while Premium also lets you work in multiple currencies.

You can add a button to invoices for accepting cards via Stripe and direct bank payments via GoCardless. Rather than paying transaction fees to Xero, each accepted card payment or Direct Debit transfer incurs a cost via Stripe or GoCardless.


Monthly fee: £15-£55 + VAT

Stripe payments: 1.5% + 20p for consumer UK cards, 1.9% + 20p for premium UK cards, 2.5% + 20p for EEA cards, 3.25% + 20p for international cards; 2% currency conversion

GoCardless transfers: Fees via GoCardless

It’s possible to add a payment button on invoices that’s handled by another card processor – Xero is flexible like that.

That being said, Xero reportedly has a steep learning curve that some only find worth the time if they use it for a larger company. But the interface has improved over the years, and it is generally a solid system for keeping the books in order.

Integrated payments: Stripe (Visa, Mastercard, Apple Pay, Google Pay), GoCardless bank transfers

Best for: Xero users who’d like their invoices integrated with bookkeeping.

PayPal – simplest for PayPal users

Our rating
  • No monthly cost, no contract

  • Zettle handles payment processing

  • Payouts in 1-2 working days

  • Comes with free POS features

PayPal invoices have been the easiest way for sole traders and small businesses to send invoices online for a couple of decades, so it would be amiss not to mention it. Anyone with a PayPal Business account can download the PayPal Business app to create and send invoices via email.

Image: MobileTransaction

Two invoice-making screens in the PayPal Business app

It’s very straightforward to create an email invoice in the PayPal Business app.

Customisation options are not the most extensive, but they cover both the legal requirements for invoices and additional extras like allowing partial payments, tips, postage cost, doscounts and custom terms and conditions. Like most invoice apps, you can itemise the invoice, attach a reference, note to the customer and VAT details. For repeat billing, you can save customers and invoiced items so you don’t have to spell out the same service for the next invoice.

Clients receive the invoice via email, with buttons to pay straight away via their PayPal account, debit or credit card, or PayPal Pay Later (credit option). Since many people are familiar with the PayPal brand, they are likely to trust these methods and pay faster.

Transactions clear right away in your online PayPal Business account, not a bank account, minus transaction fees.


Monthly cost: None

Transaction fee: 2.9% + 30p for domestic Visa and Mastercard

If you need the money in your bank account, you must transfer it from the app to the business bank account associated with the PayPal account.

“I’ve used PayPal invoices many times because some clients prefer it (mostly for convenience), but I do hate the fees. I much prefer another invoice solution that doesn’t eat into my margins just to get paid.”

– Emily Sorensen, Senior Editor, MobileTransaction

What about fees? Well, that’s the hardest part to swallow. PayPal isn’t cheap even for domestic consumer cards. The standard rate is 2.9% + 30p per card transaction, plus 1.29% for EEA cards or  1.99% for other international cards, if a non-UK card was used. There is also a currency conversion fee of 3% if at any point you receive a foreign-currency amount into your GBP account.

Integrated payments: PayPal (Visa, Mastercard, American Express)

Best for: Existing PayPal merchants who want to bill clients in the most convenient way possible, despite higher transaction fees.

Other invoice apps

Lots of invoicing apps are available to the UK, but many have flaws.

For example, some invoice apps are created for the North American market, are buggy, have limited features, or use Stripe for payment processing – known for their slow settlement (about a week) to UK bank accounts.

Alternatively, you can sign up for an online business current account with invoicing. For example, Monese business accounts has basic invoice features. Starling Bank’s Business Toolkit includes invoicing software only accessed in a web browser.

We also tested Tide Invoicing – from another digital bank – which was overall easy to use, but required a subscription for features we considered essential.