London is the global capital of financial technology. The proximity of the City’s ancient financial institutions to the coding talent of Shoreditch has created a unique ecosystem where disruption has evolved into dominance. In 2026, the focus is on the deep infrastructure, including payment rails, compliance engines, and core banking systems, that power the world’s money.
London’s founders are building the operating systems for global commerce, backed by deeper pools of capital than anywhere else on the continent. Here are the 10 FinTech startups in London you need to watch.
Revolut
Led by Nik Storonsky, Revolut has transcended the neobank label to become a global financial super-app. With a valuation exceeding $45 billion and serving over 45 million customers, the company has demonstrated that a digital-first bank can be highly profitable. They have aggressively expanded beyond simple currency exchange into crypto trading, stock investing, and travel experiences. Their recent banking license approvals in the UK and Mexico signal a mature phase of regulatory integration, positioning them to compete directly with titans like HSBC and JPMorgan rather than just other startups.
Checkout.com
Guillaume Pousaz founded Checkout.com to fix the fragmented world of online payments. The company creates the underlying infrastructure that allows global giants like Netflix, Sony, and Shein to accept payments in any currency with high acceptance rates. By offering a unified platform that handles everything from acquiring to fraud detection, they serve as the invisible engine of the digital economy. Despite market corrections, they remain one of Europe’s most valuable private tech companies, actively deploying capital to dominate the embedded finance sector.
Thought Machine
Paul Taylor, a former Google engineer, founded Thought Machine to kill the mainframe. Their product, Vault, is a cloud-native core banking engine that allows banks to run their ledgers on modern code rather than legacy systems from the 1980s. Major institutions like Lloyds Banking Group, Standard Chartered, and JPMorgan Chase have adopted Thought Machine to modernise their stack. With a valuation of $2.7 billion, they are the standard-bearers for the infrastructure modernisation wave sweeping the global banking industry.
Zilch
Philip Belamant founded Zilch to reinvent credit with a radical ad-subsidised model. Unlike traditional Buy Now, Pay Later firms that rely solely on merchant fees or late charges, Zilch creates an ad network on top of the payments layer, allowing retailers to subsidise the cost of credit for the consumer. This ASAP (Ad-Subsidised-Payments) model has driven explosive growth, with the company reaching profitability ahead of schedule. They are currently eyeing a massive IPO, aiming to disrupt the trillion-dollar advertising market as much as the credit market.
Quantexa
Vishal Marria founded Quantexa to solve the data problem in financial crime. Their Decision Intelligence platform utilises AI to connect billions of data points from internal bank records to external corporate registries, creating a contextual view of risk. This enables banks like HSBC to identify money laundering networks and complex fraud rings that standard rules-based systems often miss. Having achieved unicorn status with a valuation of $1.8 billion, Quantexa is now expanding into the government sector, helping nations track illicit finance and supply chain risks.
GoCardless
Hiroki Takeuchi, Matt Robinson, and Tom Blomfield founded GoCardless to simplify the process of collecting recurring payments. While credit cards expire and fail, GoCardless utilises the Direct Debit and Open Banking networks to directly debit money from bank accounts. This makes them the default payment layer for the subscription economy, processing over $30 billion annually for companies like DocuSign and The Guardian. Their acquisition of open banking provider Nordigen has further cemented their position as the bank payment utility for the internet.
Marshmallow
Oliver and Alexander Kent-Braham founded Marshmallow to address the insurance needs of those the industry had left behind. They use proprietary data and machine learning to price risk more accurately for expats, young drivers, and gig workers, groups that have traditionally been penalised by legacy insurers. By building their own risk engine rather than relying on standard actuarial tables, they have reached a valuation of over $1.2 billion. They represent the new wave of inclusive insurtech, proving that serving underserved markets is not charity, but a massive commercial opportunity.
Primer
Paul Anthony and Gabriel Le Roux, former PayPal employees, built Primer to be the “OS” for payments. Their no-code automation platform allows merchants to connect and manage dozens of different payment services, such as Stripe, Klarna, and PayPal, through a single integration. This gives retailers the freedom to switch providers instantly to get the best rates or achieve the best success metrics without rewriting code. Backed by Iconiq Growth, they serve as the strategic layer that sits above payment processors, providing merchants with total control over their checkout stack.
Griffin
David Jarvis and Allen Rohner founded Griffin to build a bank specifically for fintechs. In 2024, they received their full UK banking license, allowing them to offer Banking as a Service BaaS with the regulatory certainty of a fully licensed bank. Unlike intermediaries who rent licenses, Griffin holds the deposits and runs the ledger itself. This full-stack approach appeals to companies that need to embed financial products, such as savings accounts or client money wallets, without navigating the compliance nightmare themselves.
Paddle
Christian Owens founded Paddle to handle the headache of selling software globally. Instead of just processing payments, Paddle acts as the Merchant of Record, taking legal responsibility for the transaction. This means they automatically handle VAT, sales tax, and compliance in every country where a sale is made. For SaaS companies, this removes the need to hire a massive finance team to track global tax laws. With a valuation of $1.4 billion, Paddle is the specialised infrastructure enabling the global software-as-a-service boom.