API infrastructure Companies in Europe

Pieter van der Does and Arnout Schuijff had already built and sold one payments company when they sat down in 2006 to start again. The result was Adyen — the name literally means "start over" in Surinamese — and the premise was simple: instead of stitching together the same fragmented payment infrastructure everyone else was using, they would build the whole thing themselves from scratch. That decision, made in an Amsterdam office nearly two decades ago, is still the reason Adyen is different. Most payment companies are assemblers — they buy a gateway here, a processor there, bolt them together and hope for the best. Adyen owns its own technology stack end to end, which means a merchant integrating once gets access to card processing, local payment methods, point-of-sale terminals, and real-time settlement data through a single platform. No middle layers, no reconciliation headaches, no finger-pointing between vendors when something breaks. The client list tells you everything about where Adyen sits in the market. McDonald's, Spotify, Microsoft, LVMH, H&M — these are companies with serious payment volumes and zero appetite for systems that don't work. Adyen became the default choice for enterprises that had outgrown the limitations of traditional payment stacks and needed something that could handle global scale without buckling. Since going public on Euronext Amsterdam in 2018, Adyen has grown into one of Europe's most valuable technology companies, with around 4,300 employees across 23 countries and net revenue of just under €2 billion in 2024. It remains headquartered in Amsterdam and consistently profitable — a combination that's rarer in fintech than it should be. For businesses that treat payments as infrastructure rather than an afterthought, Adyen is the benchmark everything else gets measured against.

Adriaan Mol built Mollie's first backend while living with his parents in the Netherlands in 2004. No investors, no office, no team — just a founder and an idea that small businesses deserved a payment integration that didn't require a team of lawyers and a six-month setup process. He bootstrapped it for over fifteen years before taking outside funding in 2019. By then, Mollie had already grown into one of the most important payment platforms in European e-commerce, entirely on the back of a product that developers actually liked using. The proposition is straightforward: one API, one dashboard, and access to the payment methods that actually matter across Europe. That means iDEAL in the Netherlands, Bancontact in Belgium, Klarna and SEPA Direct Debit everywhere, alongside cards, Apple Pay, and a growing list of local methods that would otherwise require separate integrations and separate acquirer relationships. Mollie handles the compliance, the fraud monitoring, and the settlement complexity. Merchants get a clean interface and a single invoice. For the 250,000 businesses using Mollie today — ranging from Gymshark and Wild to local bakeries and market stalls, as CEO Koen Köppen regularly points out — the appeal is less about feature lists and more about what they don't have to think about. European payments are fragmented by design. Every country has its preferred methods, its own regulatory quirks, its own consumer habits. Mollie's job is to make that invisible. The numbers from 2024 reflect a company that has found its model. Revenue reached €214 million, up 28% year on year, with gross profit growing 30% to €115 million and the company returning to positive EBITDA for the first time since 2018. Mollie raised a total of $940 million in funding and was valued at $6.5 billion following its 2021 Series C led by Blackstone. The most significant recent development is the acquisition of GoCardless in December 2025 — bringing the UK-based direct debit specialist into the Mollie group and substantially expanding its recurring payments and bank transfer capabilities across Europe. Combined, the two companies cover a considerable share of European e-commerce payment infrastructure. Mollie is still headquartered in Amsterdam, with around 900 employees across offices in Ghent, London, Lisbon, Munich, Milan, Paris, and beyond.

Omnius is a European fintech infrastructure player that builds the plumbing for digital finance. Rather than launching consumer apps or chasing trends, the company focuses on giving financial institutions and fintech operators the core technology to move faster. The platform handles payment processing, account management, and the underlying APIs that let banks and non-banks operate at scale without reinventing the wheel. What distinguishes Omnius in a crowded infrastructure market is its pragmatic approach to complexity. European banks still manage legacy core systems alongside new digital channels—a messy, expensive reality most fintech companies ignore. Omnius doesn't fight that; it sits in the middle, connecting old and new, and abstracts the chaos away from the business logic above it. The company targets institutions that need to modernize faster than their technology stacks allow. That includes challenger banks that need banking-as-a-service foundations, traditional banks building new digital channels, and fintech companies that want to scale without owning every layer. It's unsexy infrastructure work—the kind that doesn't generate headlines but quietly powers the financial services layer that consumers interact with. In the European fintech stack, Omnius occupies a critical but overlooked position: the vendor that lets faster companies stay fast, and slower ones move at all.

Nexi is what happened when Italy decided to build a payments champion. The company's roots run through decades of bank-owned card infrastructure — the CartaSi and ICBPI lineage that processed Italian card payments on behalf of the banking system — before private equity firms Advent, Bain, and Clessidra reshaped it into a company and took it public on Borsa Italiana in 2019. Then came the two deals that defined it: the merger with SIA, Italy's interbank payments infrastructure, and the acquisition of Denmark's Nets, both closed in 2021. The result was "The European PayTech" — a group operating in more than 25 countries with around 9,200 employees, spanning merchant acquiring, card issuing for banks, and national payment infrastructure from Italy to the Nordics to Poland, where Nets' acquisitions of Przelewy24 and Dotpay sit inside the group. The strategy was scale through consolidation, and for a while the market believed in it. It no longer does, and March 2026 was the moment that became undeniable. Nexi's full-year 2025 results — revenue of €3.58 billion, EBITDA of €1.9 billion, growth of just 2.1% — arrived with a €3.7 billion writedown on previously acquired businesses, chiefly Nets, and guidance that 2026 would be flat, with growth not returning until 2028. The stock fell more than 20% in a day to a record low. CEO Paolo Bertoluzzo's framing to investors was unusually candid for the genre: Nexi was transitioning from a growth company to one that produces steady cash flows — "you don't have to believe we can go to the moon" — with a dividend hiked 20% and €1.1 billion in shareholder returns planned through 2028 as the consolation. His defence of the writedown was equally frank: Nexi bought companies at high prices, but paid in shares that were then worth six times their current value. The ownership structure completed its own transition in early 2026. Advent and Bain, the private equity firms that built and listed the company, sold their remaining stake in February — leaving Hellman & Friedman and CDP, the Italian state investor, as the two anchor shareholders at roughly a fifth each. The parallel with Worldline is hard to miss: Europe's two great payments roll-ups of the 2019–2021 era have both ended the cycle written down, growth-challenged, and anchored by state-linked capital — Nexi without the compliance scandal, which is a meaningful distinction, but with the same underlying lesson about buying growth with expensive shares. CVC explored a bid in 2024, sending the shares up 19% in a day; nothing came of it, though the episode established that the company is viewed as acquirable. Leadership turned over with the strategy: Bernardo Mingrone, Nexi's long-serving finance chief, succeeded Bertoluzzo as CEO in 2026, presenting his first half-year results in July. The growth initiatives under way are real if unglamorous — Zippay, a person-to-person payment service built on Nexi infrastructure launching in Ireland with AIB, Bank of Ireland, and PTSB; integration of the European wallet Wero into German e-commerce; a Visa partnership on managed card issuing for German banks; and the €105 million acquisition of Banca Popolare di Sondrio's merchant book, continuing the model of buying banks' payment operations that built the company. Nexi remains one of Europe's largest payment processors and the default infrastructure of Italian digital payments. The question its own guidance poses is whether that is a platform for renewed growth from 2028, or simply a very large utility returning cash to patient shareholders. The current share price says the market has priced the utility.

Embat is a European fintech platform built for the era when payments moved beyond the checkout. Founded on the principle that modern businesses need payment infrastructure that speaks their language—not the other way around—Embat offers a composable payments stack designed for developers and merchants who refuse to settle for legacy constraints. The platform combines payment orchestration, processing, and settlement into a single, modular system. Rather than forcing clients into rigid vendor relationships, Embat lets companies plug in their preferred processors, acquirers, and gateway partners while maintaining unified visibility and control. This flexibility appeals to enterprises and merchants tired of vendor lock-in and technical debt. What sets Embat apart in the crowded European payments landscape is its developer-first design philosophy. The company recognizes that payments sit at the intersection of multiple systems—loyalty, inventory, subscriptions, marketplaces—and builds its API architecture accordingly. This contrasts sharply with older payment solutions that treat payments as an isolated transaction layer rather than a core business platform. Embat occupies a distinct position between monolithic payment processors and lightweight API providers. It's built for companies that have outgrown commodity payment gateways but don't want to stitch together five different vendors to get what they need. In the increasingly competitive European fintech market, Embat represents the modern infrastructure play: solving real operational complexity for merchants and enterprises through intelligent, flexible payment technology.

Most open banking aggregators want your data. That is the business model: connect to the banks, pull the transactions, store them, enrich them, and sell the enriched product back. Enable Banking built the opposite. The company describes itself as the postman of your data — it moves financial information from the bank to the customer's application and does not retain, process, or build models on what passes through. For a fintech that considers its transaction data a competitive asset, or a customer with strict data residency requirements, that neutrality is the entire pitch. Joonas Tomperi and Fedor Tyurin founded the company in Espoo in 2019, at the point where PSD2 had legally opened European bank APIs but had not made them usable. Each bank interpreted the standard differently, each shipped its own authentication quirks, and each updated on its own schedule. The regulation created the right; someone still had to build the plumbing. Enable Banking started with Finland and the Nordics and expanded outward, and now connects to more than 2,700 banks across 30 European countries through a single PSD2-compliant API — account information from all of them, and payment initiation from over 1,500. What makes the company genuinely unusual is its scale relative to that coverage. Enable Banking has raised roughly €600,000 in total, in a single seed round in 2022 led by Wellstreet and Forward VC, and employs somewhere between fourteen and seventeen people distributed across seven countries. Tink sold to Visa for €1.8 billion with 500 employees. TrueLayer has raised hundreds of millions. Enable Banking is covering comparable European ground with a team that would fit around one table, which says something about how much of open banking infrastructure is disciplined engineering rather than capital. The company holds its own Account Information Service Provider registration, supervised by Finland's FIN-FSA — which means other companies can build on top of its licence rather than obtaining their own. That is the model behind open-banking.io, the Danish developer tool that resells Enable Banking access at €3 per month without customers needing eIDAS certificates. It is also why Enable Banking's no-data-retention architecture matters structurally: because the platform never holds readable customer data, the companies building on it can make stronger privacy guarantees than they otherwise could. Two smaller details are revealing about who this is built for. Enable Banking runs a balanced split between business and consumer accounts — roughly half of its ten million monthly API calls come from each, where most early open banking providers targeted consumer accounts only and treated corporate banking as an afterthought. And it offers a live production environment for testing without requiring a contract, which is a small thing that tells you the company expects developers to evaluate it by using it rather than by booking a call. Tomperi now chairs the board of Fintech Finland, the national industry association.