France has a broad fintech development market, ranging from focused financial software teams to large technology consultancies with dedicated banking practices. The companies below cover custom fintech platforms, digital banking, payments, lending, trading technology, core modernization, financial APIs, and regulated software engineering.
1. Itexus
Itexus builds custom fintech software for banks, brokers, fintech companies, investment firms, and other financial organizations. Typical projects include digital banking, lending, payments, wallets, wealth management, and trading. The team also builds onboarding, KYC, and financial analytics, and takes on complex integrations and modernization of existing financial platforms. Itexus has development offices in Europe and the US and works with financial companies across Europe, including France. It has delivered more than 300 fintech projects in 23 countries.
Key Facts
- Best for: Custom fintech products and complex financial platforms
- Core services: Fintech software development, fintech app development, legacy modernization, AI consulting, staff augmentation
- Specialization: Banking, trading, wealth management, payments, lending
- Technologies: Java, .NET, TypeScript, Python, cloud infrastructure
- Geographic coverage: France and the wider European market
- Notable strength: Experience with regulated, integration-heavy financial software
Contact Information
- Website: itexus.com
- Email: moc.suxeti@ofni
- Address: Twarda 14, 00-824 Warszawa, Poland
- LinkedIn: www.linkedin.com/company/itexus
- Facebook: www.facebook.com/itexus
- Twitter: x.com/ItexusSoft
- Instagram: www.instagram.com/itexus.soft
2. Sopra Steria
Sopra Steria runs a large financial services practice that serves banks and insurers in France. Its teams build digital lending journeys, regulatory systems, and customer-facing financial services. They also work on open finance, APIs, data and AI, and the modernization of banking IT. The company sells its own financial software too, including Sopra Financing Software and other banking technology. Banks with older systems, heavy regulatory demands, or many applications to manage get both engineering skill and sector knowledge here.
Key Facts
- Best for: Large banking and financial transformation programs
- Core services: Financial software, systems modernization, open finance, API development, data and AI
- Specialization: Banking, insurance, lending, compliance
- Location: Multiple offices across France
- Notable strength: Combination of financial software products and custom technology services
Contact Information
- Website: www.soprasteria.com
- Address: ZAC de la Grande Plaine Bât C 6 rue Brindejonc des Moulinais BP15872, 31506 Toulouse
- LinkedIn: www.linkedin.com/company/soprasteria
- Instagram: www.instagram.com/soprasteria_group
- Twitter: x.com/soprasteria_fr
3. Capgemini
Capgemini pairs software engineering with a dedicated banking technology practice. It modernizes core banking, builds cloud-native applications, APIs, and microservices, and integrates applications for financial firms. It also helps banks design and roll out modern core platforms. That suits projects that go beyond a single mobile app and reach into wider banking infrastructure. Capgemini has a large presence in France, with its French headquarters in Issy-les-Moulineaux and offices in many regions.
Key Facts
- Best for: Enterprise banking modernization
- Core services: Custom applications, core banking, cloud development, APIs, application integration
- Specialization: Banking technology and large enterprise systems
- Location: Extensive office network across France
- Notable strength: Ability to combine software engineering with large transformation programs
Contact Information
- Website: www.capgemini.com
- Phone: +33 1 57 99 00 00
- Address: 147 Quai du Président Roosevelt, 92130 Issy-les-Moulineaux, France
- LinkedIn: www.linkedin.com/company/capgemini
- Facebook: www.facebook.com/capgeminifrance
- Instagram: www.instagram.com/capgeminifr
4. Theodo FinTech
Theodo FinTech is one of the more specialized fintech teams in France. It designs and builds digital platforms for banks, fintech companies, investment funds, asset managers, and private banks. Projects include banking apps, digital lending journeys, banking APIs, open finance products, and embedded finance. The team also modernizes existing technology stacks. Clients include Bpifrance, Qonto, Swan, Yomoni, and Milleis. The Paris team handles product strategy and design as well as engineering, so its role goes beyond technology consulting.
Key Facts
- Best for: Fintech startups, banks, and new digital financial products
- Core services: Fintech development, mobile banking, APIs, embedded finance, platform modernization
- Specialization: Open finance, payments, lending, investment and banking software
- Location: Paris, France
- Notable strength: Dedicated Theodo FinTech engineering practice
Contact Information
- Website: www.theodo.com
- LinkedIn: www.linkedin.com/company/theodo
5. GFT Technologies
GFT has long roots in banking technology and runs a French office in Niort. Its financial services team works in banking, capital markets, asset management, and insurance. For banks, it builds digital banking, open banking infrastructure, API-first systems, and cloud-native core platforms. It also delivers AI and legacy modernization. GFT has its own banking accelerators, BankStart and BankLiteX, which help institutions launch or rebuild digital banking. It is a good choice when custom code must connect to existing banking platforms or third-party core systems.
Key Facts
- Best for: Digital banking and core modernization
- Core services: Banking software engineering, APIs, cloud, AI, core transformation
- Specialization: Banking, capital markets, asset management
- Location: Niort, France
- Notable strength: Long-standing focus on financial technology
Contact Information
- Website: www.gft.com
- Address: 18 Avenue Leo Lagrange, 79000 Niort, France
- LinkedIn: www.linkedin.com/company/gft-technologies-france
- Facebook: www.facebook.com/gfttechnologies
- Instagram: www.instagram.com/GFT_Tech
- Twitter: x.com/gft_tech
6. CGI
CGI works with French banks and financial institutions on application development, systems integration, and core modernization. It also covers payments, data, cloud, and wider technology change. Its current banking projects in France use full-stack Java, React, Angular, and .NET, along with data engineering and mainframe development for major banks. CGI also owns financial products for payments, trade finance, credit, compliance, and wealth management.
Key Facts
- Best for: Complex banking systems and enterprise financial software
- Core services: Application development, system integration, modernization, payments, cloud
- Specialization: Retail banking, investment banking, payments, wealth management
- Location: Offices across France
- Notable strength: Custom delivery combined with proprietary banking solutions
Contact Information
- Website: www.cgi.com
- Phone: 04 42 97 22 20
- Address: 355 Rue Louis de Broglie, Aix-en-Provence 13290
- LinkedIn: www.linkedin.com/company/cgi
- Instagram: www.instagram.com/cgi_france
- Twitter: x.com/cgi_fr
7. Inetum
Inetum helps financial institutions build, integrate, and modernize applications and digital platforms. Its work spans payments, open finance, risk systems, and cloud-native banking technology. The company covers the whole software lifecycle: it builds and integrates applications, modernizes legacy systems, and runs them after launch. In financial services, it works on digital onboarding, core banking modernization, payment systems, regulatory requirements, and fraud technology. Inetum is headquartered in Saint-Ouen-sur-Seine and has a large French operation.
Key Facts
- Best for: Application modernization in established financial institutions
- Core services: Application development, integration, modernization, payments, cloud
- Specialization: Banking and financial services
- Location: Saint-Ouen-sur-Seine, France
- Notable strength: Full application lifecycle coverage
Contact Information
- Website: www.inetum.com
- Phone: +33 (0)1 44 04 50 00
- Address: 5-7 Rue Touzet Gaillard, 93400 Saint-Ouen, France
- LinkedIn: www.linkedin.com/company/inetum
- Instagram: www.instagram.com/inetum_world
- Twitter: x.com/inetum_world
8. Accenture
Accenture's French banking practice handles technology delivery as well as strategy and business transformation. Its work includes core banking modernization, open banking and open finance, payments, digital channels, lending technology, and cloud banking systems. It hires software engineers and technical architects specifically for financial services, including core banking and digital payments work. Its size suits banks and larger fintech companies that need engineering together with architecture, integration, regulatory, data, or organizational change.
Key Facts
- Best for: Large financial institutions and multi-system transformations
- Core services: Banking software implementation, core modernization, open finance, cloud, integration
- Specialization: Banking and financial services
- Location: Paris, Lyon, Nantes, Sophia Antipolis
- Notable strength: Ability to combine engineering with large-scale transformation
Contact Information
- Website: www.accenture.com
- Address: 118 Avenue de France, 75013 Paris, France
- Phone: +33 1 53 23 55 55
9. Talan
Talan was founded in France and offers technology delivery alongside consulting, data, AI, cloud, and application services. Banking and financial services are among its established sectors, and its teams run digital transformation programs for financial institutions. Its application team builds and integrates software. The wider technology team handles architecture, data integration, cloud platforms, and large transformation projects. With offices in Paris and several other French cities, Talan works well for financial companies that want a local team with international backup.
Key Facts
- Best for: Banking projects combining software, data, and transformation
- Core services: Application services, cloud, data, AI, systems integration
- Specialization: Banking and financial services
- Location: Paris and multiple French cities
- Notable strength: French delivery presence combined with international operations
Contact Information
- Website: www.talan.com
- LinkedIn: www.linkedin.com/company/talan
- Facebook: www.facebook.com/talan
- Instagram: www.instagram.com/talan_world
- Address: 85 r Pierre Berthier, 13290 Aix en Provence
- Phone: +33 4 42 12 74 75
10. Groupe SII
Groupe SII provides software engineering and technology consulting from a large operation in France. In banking and finance, it currently does full-stack Java and Angular development for critical business applications. Its developers handle requirements analysis, backend code, user interfaces, testing, maintenance, and the evolution of complex information systems. Its Île-de-France team works with major companies on digital transformation, engineering, and technology programs.
Key Facts
- Best for: Engineering capacity for banking applications
- Core services: Software development, digital transformation, technology consulting
- Specialization: Enterprise and critical applications
- Financial capabilities: Banking and finance software development
- Location: Île-de-France and other French regions
Contact Information
- Website: sii-group.com
- Address: 8 Rue des Pirogues de Bercy, 75012 PARIS
- LinkedIn: www.linkedin.com/company/sii
- Instagram: www.instagram.com/Groupe_SII
11. Aubay
Aubay focuses on application services and digital transformation, including work for banks. Its French teams build and maintain financial applications, such as software for treasury management and regulatory reporting. Current banking work covers application updates, coding, unit and functional testing, deployment support, and modernization of existing systems. Aubay fits established banks, financial institutions, and fintech teams that need developers who can work inside complex existing systems. It has French offices in Boulogne-Billancourt, Courbevoie, Nantes, Bordeaux, and Lyon.
Key Facts
- Best for: Banking application development and maintenance
- Core services: Application development, digital transformation, software engineering
- Specialization: Critical enterprise applications
- Financial capabilities: Treasury, regulatory and banking systems
- Location: Multiple French offices
Contact Information
- Website: aubay.com
- E-mail: moc.yabua@atad-tcatnoc
- Phone: +33 (0)1 46 10 67 67
- Address: 13 rue Louis Pasteur, 92100 Boulogne-Billancourt, France
- LinkedIn: www.linkedin.com/company/aubay-data-n-ai
12. ACCENSEO
ACCENSEO is a Paris-based software engineering and IT consulting company that builds custom applications for financial firms. It modernizes transaction platforms and moves legacy systems to cloud-native architectures. It also connects financial applications to core banking systems and third-party services. Other projects include customer portals, payment workflows, reporting tools, and reconciliation systems.
Companies with established financial infrastructure can use ACCENSEO for both new software and updates to existing systems. The team covers architecture and engineering, integration, cloud infrastructure, maintenance, and ongoing application support.
Key Facts
- Best for: Custom fintech platforms and financial system modernization
- Core services: Custom software development, application modernization, solution integration, cloud services, maintenance
- Specialization: Financial services software and transaction platforms
- Financial capabilities: Payment workflows, reporting, reconciliation, core banking integrations
- Location: Paris, France
Contact Information
- Website: www.accenseo.com
- Email: moc.oesnecca@atsoc-ad.esoj
- Address: 60 Rue François 1er, 75008 Paris, France
- LinkedIn: www.linkedin.com/company/accenseo
13. VISEO
VISEO combines custom software development with financial markets technology. In France it modernizes business applications, builds custom software, and maintains applications. It also works on data, AI, cloud, cybersecurity, and trading platform transformation. In financial services, it knows capital markets technology and Murex well and runs complex IT transformations for banks and financial firms. VISEO is a strong choice when custom code must connect to trading, risk, finance, or established enterprise platforms. It is headquartered in Boulogne-Billancourt with offices in several French cities.
Key Facts
- Best for: Capital markets and enterprise finance technology
- Core services: Custom development, application modernization, managed services, data and AI
- Specialization: Trading platforms and financial systems
- Location: Seven locations in France
- Notable strength: Murex and capital markets technology capabilities
Contact Information
- Website: www.viseo.com
- Phone: +33 01 56 56 71 00
- Address: 94-96, Rue de Paris, 92100 Boulogne-Billancourt
- LinkedIn: www.linkedin.com/company/viseo
- Instagram: www.instagram.com/viseogroup
14. Expleo
Expleo builds, tests, and maintains enterprise web and mobile applications, and banking and financial services are among its main sectors. The company says it has built more than 200 critical applications over the past decade in banking, insurance, financial services, and other industries. Its banking team also handles cloud modernization, digital channels, legacy modernization, system integration, quality engineering, and compliance. Expleo has a large, active French team backed by its global engineering network.
Key Facts
- Best for: Regulated financial platforms requiring engineering and quality assurance
- Core services: Application development, cloud modernization, DevSecOps, testing, system modernization
- Specialization: Banking and financial services
- Location: France
- Notable strength: Software development combined with extensive testing and quality engineering
Contact Information
- Website: expleo.com
- Address: ZI de la Frayère, 4 allée des Cormorans, 06150, Cannes
- Phone: +33 458 052 556
- Email: moc.puorgoelpxe@ecnarf_ofni
- LinkedIn: www.linkedin.com/company/expleo-group
- Facebook: www.facebook.com/expleogroup
- Instagram: www.instagram.com/expleo_group
- Twitter: x.com/ExpleoGroup
15. ALTEN
ALTEN provides IT services and technology engineering to banks, finance companies, and insurers. In finance, it builds mobile banking apps, integrated payment systems, open banking solutions, and credit-risk tools. It also delivers transaction monitoring technology and customer data platforms. One published French digital banking project shows full-stack developers handling application architecture and development alongside UX and functional specialists. France is still ALTEN's home market, with 16 strategic locations and a large local engineering team.
Key Facts
- Best for: Large-scale banking engineering programs
- Core services: IT services, application development, digital banking, payments, data
- Specialization: Banking, finance and insurance
- Location: 16 locations across France
- Notable strength: Large French engineering footprint with dedicated financial sector capabilities
Contact Information
- Website: www.alten.com
- Address: 21 bis boulevard Jean Jaurès, 92100 Boulogne-Billancourt
- Phone: +33 1 46 08 70 00
- LinkedIn: www.linkedin.com/company/alten
- Facebook: www.facebook.com/AltenFrance
- Instagram: www.instagram.com/alten_group
- Twitter: x.com/alten_france
Conclusion
France offers a varied selection of fintech software development companies, from focused product engineering teams to large technology groups working with banks and financial institutions. The right choice depends on the project, whether it involves launching a new fintech product, modernizing legacy banking systems, building payment infrastructure, improving trading platforms, or integrating financial applications with existing systems. Comparing each company by fintech expertise, technical capabilities, delivery model, and experience with regulated financial software can help narrow the options to the most suitable development partner.