Top 10 SaaS Companies in the UK 2026

UK companies don’t just use software. They build loads of it.

Accounting packages in Newcastle. AI-powered security in Cambridge. UK-built platforms now run payroll, payments, hotel pricing and fraud checks for businesses across the globe, and the numbers prove it. Sage booked £2,062 million in underlying revenue in the nine months to June 2026, and Checkout.com reached $750 million in annualized net revenue this year while staying profitable.

Investment keeps pouring in too. According to Beauhurst, UK SaaS companies raised £5.04 billion in 2024, up 20% year on year, and SaaS made up 29% of all UK equity funding in the first quarter of 2025.

Yet a large funding round doesn’t make a vendor worthy of your business. Some of the companies here are listed giants. Others are privately held specialists that dominate one niche, from core banking to hotel revenue data. All of them share one thing: a subscription product that customers keep renewing.

This guide looks at the top 10 SaaS companies in the UK for 2026, what each one does best and who it suits.

Why Businesses Choose SaaS Companies in the UK

Deep Talent in Finance and AI

London, Cambridge and Oxford give software companies access to talent with strong engineering and research credentials. You’ll see that reflected in products built around machine learning, payments and data, where many SaaS companies in the UK now compete with the best in the world.

Regulation-Ready Products

Oversight from the FCA, GDPR-style data rules and strict banking standards mean UK vendors grow up with compliance, audit trails and security built into their products from day one. That helps them win deals with banks, insurers and the public sector.

Global Reach From a Single Base

Most of the companies on this list sell far beyond Britain. A UK base gives them easy access to Europe, a useful time zone overlap with the US and English-language markets worldwide. In other words, you get a vendor that already knows how to support multi-country rollouts.

Predictable Subscription Costs

SaaS turns large upfront software bills into monthly or annual fees. Those fees include updates, hosting and security patches, so your IT team can focus on using the software rather than maintaining it.

Top 10 SaaS Companies in the UK at a Glance

Rank	Name	Core segment	Key 2026 figure
1	Sage	Accounting, payroll and ERP for SMBs	£2,062m underlying revenue in 9 months to June 2026, up 11%
2	Checkout.com	Online payments platform	$750m annualized net revenue, up 28%
3	Darktrace	AI cybersecurity	Nearly 10,000 customers
4	Synthesia	AI video generation	$4bn valuation after $200m round (Jan 2026)
5	Quantexa	Decision intelligence and fraud detection	900+ employees; Gartner MQ Leader 2026
6	Thought Machine	Cloud-native core banking	Revenue past $100m, up 57%
7	GoCardless	Bank payments and direct debit	£79.2bn processed in FY25; acquired by Mollie in 2026
8	Lighthouse	Hotel commercial intelligence	80,000+ hotels in 185 countries
9	Paddle	Billing and merchant of record for software	6,000+ software companies sell through it
10	Starling (Engine)	Banking-as-a-service platform	Engine revenue £10.9m, up 25% (FY to March 2026)

Top 10 SaaS Companies in the UK (2026)

Here’s who made the list, with what they do, their latest numbers and who should consider them.

1. Sage

Founded in 1981, Sage is easily the UK’s most recognizable business software company. Headquartered in Newcastle upon Tyne and listed on the London Stock Exchange, it sells accounting, payroll, HR and ERP software to small and mid-sized businesses. Sage Intacct and Sage Accounting are its flagship cloud products.

Sage’s latest results cover the nine months to June 30, 2026. Underlying total revenue rose 11% to £2,062 million, and recurring revenue reached £2,002 million. Sage Business Cloud revenue grew 15% to £1,762 million, while cloud native revenue jumped 25% to £794 million. Software subscription penetration reached 84%, and Sage expects organic revenue growth above 9% for FY26.

Key Sage Solutions
✔ Sage Intacct cloud financial management
✔ Sage Accounting for small businesses
✔ Payroll and HR software
✔ AI tools built into finance workflows

Best for: Small and mid-sized businesses that want proven, UK-supported finance and payroll software.

2. Checkout.com

Founded in 2012 and headquartered in London, Checkout.com gives online businesses a global payments platform they can use to accept, process and pay out money in multiple currencies through a single integration. It works with large enterprise merchants rather than your local corner shop.

In September 2026, Checkout.com said its annualized net revenue had hit $750 million, up 28% year on year. It expects total payment volume of about $480 billion in 2026 and adjusted EBITDA of roughly $150 million, having stayed profitable since 2024. The business serves more than 1,700 enterprise merchants, employs 2,300 people and operates in 56 countries. The US is now its fastest-growing region, with processing volumes up more than 120% year to date.

Key Checkout.com Solutions
✔ Online card and local payment acceptance
✔ Payouts and issuing
✔ Fraud detection tools
✔ Acquiring licenses across key markets

Best for: Large online merchants that process high volumes across several countries.

3. Darktrace

Darktrace was founded in 2013 in Cambridge, where it still runs a major R&D center alongside another in The Hague. It uses self-learning AI to understand what normal looks like across a customer’s network, email, cloud and operational technology, then detects and responds to threats as they happen. Private equity firm Thoma Bravo took the company private in a $5.3 billion deal completed in October 2024.

Darktrace now serves nearly 10,000 customers and has more than 2,400 employees worldwide. In 2025, it acquired cloud forensics business Cado Security, and Ed Jennings became chief executive in March 2026. In July 2026, Darktrace was named a Customers’ Choice in the Gartner Peer Insights report for email security platforms for the second consecutive year.

Key Darktrace Solutions
✔ Darktrace / EMAIL
✔ Darktrace / NETWORK
✔ Darktrace / OT for industrial systems
✔ Cyber AI Analyst for automated investigations

Best for: Organizations that want AI-driven threat detection with autonomous response.

4. Synthesia

Synthesia was founded in 2017 and is headquartered at Regent’s Place in London. Its platform lets businesses create professional videos using realistic AI avatars and voices, with no cameras or studios. Its co-founders include CEO Victor Riparbelli and UCL professor Lourdes Agapito.

In January 2026, Synthesia raised $200 million in a round led by GV (Google Ventures), with Nvidia’s venture arm also taking part. The round nearly doubled its valuation to $4 billion, up from $2.1 billion a year earlier. The company says 70% of Fortune 100 companies use its product. It passed $100 million in annual recurring revenue in April 2025 and now plans to expand into interactive AI agents.

Key Synthesia Solutions
✔ AI avatar video creation
✔ Training and onboarding videos
✔ Multi-language video translation
✔ Interactive AI video agents (in development)

Best for: Large companies that need training, sales or internal videos at scale.

5. Quantexa

Quantexa was founded in 2016 by chief executive Vishal Marria and is headquartered in London. Its Decision Intelligence platform helps organizations connect siloed internal and external data to see a clear picture of people, companies and the connections between them. Banks, insurers and governments use it to detect fraud and financial crime and to assess risk.

Quantexa’s $175 million Series F round in March 2025 was led by Teachers’ Venture Growth and valued the business at $2.6 billion. It passed $100 million in ARR in 2024 and now has more than 900 employees. At its QuanCon event in March 2026, it announced a partnership with Moody’s that combines Quantexa’s graph technology with Moody’s data. It was also named a Leader in the 2026 Gartner Magic Quadrant for Decision Intelligence Platforms.

Key Quantexa Solutions
✔ Financial crime and AML detection
✔ Insurance fraud detection
✔ Entity resolution and data unification
✔ AI-assisted operational decisioning

Best for: Banks, insurers and public-sector bodies fighting fraud with large, messy datasets.

6. Thought Machine

Thought Machine is a London-based firm founded in 2014 by Paul Taylor. It develops Vault Core, a cloud-native core banking platform that lets banks run any product, from current accounts to loans, on one configurable system. With about £398 million raised, it’s one of the best-funded SaaS companies in the UK.

Its customers include JPMorgan Chase and a growing number of US lenders. In August 2026, Pathward, a South Dakota bank, selected Vault Core to replace its legacy core. Thought Machine now counts 20 banks and fintechs in the Americas as clients, six of them tier 1 banks, and its revenue has passed $100 million after a 57% year-on-year increase.

Key Thought Machine Solutions
✔ Vault Core banking platform
✔ Smart contracts for product configuration
✔ Cloud-native deployment
✔ Support for lending and payment sponsorship

Best for: Banks replacing aging core systems or launching new digital banks.

7. GoCardless

GoCardless is a London-based bank payments company led by co-founder Hiroki Takeuchi. Through direct debit and open banking, its platform lets businesses collect recurring and one-off payments directly from bank accounts, which cuts card fees and failed payments. More than 100,000 businesses use it.

Group revenue for the year to June 2025 rose 22% to £160.9 million, while payment volume doubled to £79.2 billion, helped by the Nuapay acquisition. The company posted its first adjusted EBITDA-positive quarter at the end of FY25. Dutch payments firm Mollie agreed to buy GoCardless in December 2025 and completed the deal in 2026. GoCardless keeps its own brand and CEO, and the combined group serves more than 350,000 companies.

Key GoCardless Solutions
✔ Direct debit collection
✔ Pay by Bank via open banking
✔ Recurring billing integrations
✔ Payment failure recovery tools

Best for: Subscription and invoice-based businesses that want to lower payment costs.

8. Lighthouse

Lighthouse, formerly known as OTA Insight, gives hotels commercial intelligence and is headquartered in London. Its software shows rate trends, demand signals and competitor pricing to help revenue teams set the right room rates. Sean Fitzpatrick is the company’s CEO.

More than 80,000 hotels across 185 countries use Lighthouse. In late 2024, it raised about $370 million in a growth round led by KKR, and it acquired The Hotels Network in April 2025. In January 2026, it picked up four HotelTechAwards, its sixth consecutive year of wins. In June 2026, it launched Ernest, an AI teammate that answers questions using a hotel’s data and can take actions through more than 500 integrations.

Key Lighthouse Solutions
✔ Rate Insight market intelligence
✔ Parity Insight
✔ Lighthouse BI
✔ Ernest AI assistant (beta)

Best for: Hotels and hotel groups that want data-led pricing and distribution.

9. Paddle

Paddle was founded in 2012 by Christian Owens and Harrison Rose and is based in London. It acts as a merchant of record for software companies, which means it handles payments, sales tax, billing and compliance on their behalf. As a result, small software teams can sell worldwide without building finance operations in every country.

More than 6,000 companies sell through Paddle. It has raised roughly $293 million in total, including a $200 million Series D led by KKR in 2022, and Jimmy Fitzgerald is CEO. In 2026, AI app builder Lovable launched Lovable Payments with Paddle as its merchant of record, which highlights Paddle’s push to serve companies selling AI-native software.

Key Paddle Solutions
✔ Merchant of record service
✔ Subscription billing
✔ Global sales tax handling
✔ ProfitWell revenue metrics

Best for: Software and app companies that want to sell globally without handling tax themselves.

10. Starling (Engine)

Starling Bank was founded in 2014 and is headquartered in London. It’s best known for its digital banking app, but it also runs a SaaS business, Engine by Starling, which licenses its banking technology to banks around the world. That makes it one of the few companies on this list that operates its own platform at scale while also selling it as SaaS.

In the year to March 2026, Engine doubled its client base to four, and its revenue grew 25% to £10.9 million. New customers include Tangerine, a Scotiabank subsidiary, under a 10-year contract that marks Engine’s first deal in North America. The wider Starling group reported revenue of £887 million and pre-tax profit of £217 million for the same period.

Key Engine Solutions
✔ Cloud-native core banking
✔ Mobile banking apps
✔ Proven, live banking platform
✔ Long-term licensing deals

Best for: Banks that want to launch a digital bank on a platform already proven in the UK market.

How to Choose the Right SaaS Partner

Start With the Problem

Before looking at vendors, define your problem on paper. A payments issue points to a company like Checkout.com or GoCardless, while finance and payroll pains point to Sage. Clear requirements make shortlisting much faster.

Check Financial Health

Look for vendors that are growing, profitable or well backed. More SaaS companies in the UK now publish revenue and profit figures, which helps you judge whether a vendor will still be around in five years’ time.

Review Security and Compliance

Ask about certifications, where your data will be stored and how the vendor manages incidents. This matters most in banking, insurance and healthcare, where your supplier’s weakness quickly becomes your compliance headache.

Test Integrations

Good SaaS should slot into your existing tech stack. Make sure the product connects to your CRM, accounting system or data warehouse, and ask for a trial or proof of concept before you buy.

Understand the Pricing Model

Pricing varies widely. Some vendors charge per user, others per transaction, and a few take a share of revenue. Model your costs at today’s volume and at double that volume, so you aren’t surprised as you grow.

Frequently Asked Questions About SaaS Companies in the UK

Which is the biggest SaaS company in the UK?

By revenue, Sage is the largest UK-listed SaaS company, with £2,062 million in underlying revenue in the nine months to June 2026. Checkout.com is one of the largest private ones.

Are UK SaaS companies still attracting investment?

Yes. Beauhurst data shows UK SaaS companies raised £5.04 billion in 2024, and 2026 brought deals such as Synthesia’s $200 million round at a $4 billion valuation.

Which UK SaaS company is best for my business?

There’s no single best choice for everyone. The right vendor depends on your industry, your size and the problem you need to solve, so compare two or three options against your own requirements.

Do all these companies serve UK customers?

Yes. Every company on this list is headquartered in the UK and serves UK clients, though most also sell heavily in Europe, North America and Asia.

Conclusion

The SaaS companies in the UK on this list cover a wide range of needs, from Sage’s finance software and Checkout.com’s payments platform to Darktrace’s AI-powered security and Synthesia’s video avatars. A few years ago, growth often came at the expense of profit. Many of these firms now deliver both.

If you’re choosing a vendor in 2026, start with the problem you’re trying to solve, then check each provider’s track record, security controls and pricing. The best SaaS companies in the UK are the ones that solve your problem well and keep innovating after you sign.