Banks and fintech businesses in Washington need different development partners depending on what they are building: a mobile banking app, a payment integration, or a replacement for aging software. The entries highlight relevant services, delivery models, and locations so readers can build a shortlist around their project.
1. Itexus
Itexus builds custom financial software for banks, credit unions, investment businesses, and fintech companies. Its work includes mobile banking apps, a white-label banking app, and a digital customer onboarding platform with automated KYC and KYB verification. Services cover discovery, interface design, development, testing, cloud engineering, and ongoing support.
Businesses in Washington that are open to remote delivery can hire a dedicated Itexus team or add individual specialists to their own engineers. Its published offices are in Dover, Delaware, and Warsaw, Poland. With banking project experience and flexible engagement models, Itexus fits organizations building a new product or extending existing financial software.
Key Facts
- Core services: Banking software development, custom financial software, mobile banking development, QA, DevOps, and support.
- Project experience: Customer onboarding, mobile banking, and investment applications.
- Delivery models: Dedicated teams, staff augmentation, and project delivery.
- Location: Dover, Delaware, and Warsaw, Poland; remote delivery.
Contact Information
- Website: itexus.com
- E-mail: moc.suxeti@ofni
- Facebook: www.facebook.com/itexus
- Twitter: x.com/ItexusSoft
- LinkedIn: www.linkedin.com/company/itexus
- Instagram: www.instagram.com/itexus.soft
- Address: 8, The Green, STE road, Dover, DE 19901
2. Slalom
Slalom combines business consulting with software, platform, and data engineering. It has a local office in Seattle. Its financial services practice covers banking and payments, capital markets, insurance, and wealth management. Slalom builds digital products, integrates systems, modernizes cloud setups, and designs data architecture.
Consider Slalom when a banking software project also changes internal processes or customer experience. Examples include a bank connecting several applications, rebuilding a customer-facing service, or improving the data behind its operations. Such projects need planning and implementation together. Slalom covers both, not just application coding.
Key Facts
- Core services: Product engineering, systems integration, cloud modernization, and data engineering.
- Industry focus: Banking and payments within a wider financial services practice.
- Project fit: Software programs involving technology, customer experience, and operational change.
- Location: Seattle, Washington.
Contact Information
- Website: www.slalom.com
- Twitter: x.com/slalom
- LinkedIn: www.linkedin.com/company/slalom-consulting
- Address: 255 S King St, Suite 1800, Seattle, Washington 98104
3. Jelvix
Jelvix builds banking and financial software and also offers enterprise engineering and technology consulting. Its financial work covers payment processing, investment management, process automation, and third-party API integrations. Jelvix lists Seattle among its locations, and its global headquarters is in Tallinn, Estonia.
Jelvix suits organizations that need custom financial features connected to a larger enterprise system. It can support development with dedicated teams, mobile engineering, QA, technical support, and DevOps consulting. Buyers should shortlist Jelvix when payment workflows, financial data, and existing applications need to work together.
Key Facts
- Core services: Financial software development, mobile applications, QA, and dedicated teams.
- Relevant capabilities: Payment processing, investment tools, automation, and API integration.
- Location: Seattle presence; global headquarters in Tallinn, Estonia.
Contact Information
- Website: jelvix.com
- E-mail: moc.xivlej@olleh
- Facebook: www.facebook.com/JelvixCompany
- Twitter: x.com/jelvix
- LinkedIn: www.linkedin.com/company/jelvix
- Instagram: www.instagram.com/jelvix
- Address: Kaupmehe tn 7, 10114 Tallinn, Estonia
- Phone: +1 240 507 54 71
4. EPAM
EPAM works with retail and commercial banks, investment banks, payment providers, and wealth management firms. It builds platforms, integrates APIs, modernizes systems, and handles cloud work and quality engineering. Its Bellevue office gives it a Washington location within its international delivery network.
EPAM fits banking projects with several technical workstreams, such as modernizing applications while updating their integrations and data infrastructure. Its financial services work goes beyond consumer banking into payments and capital markets. That helps institutions whose software must connect customer channels with more complex financial systems and operations.
Key Facts
- Core services: Platform engineering, API integration, modernization, cloud services, and testing.
- Financial sectors: Retail and commercial banking, investment banking, payments, and wealth management.
- Project fit: Enterprise financial software development and modernization.
- Location: Bellevue, Washington.
Contact Information
- Website: www.epam.com
- Facebook: www.facebook.com/EPAM.Global
- LinkedIn: www.linkedin.com/company/epam-systems
- Instagram: www.instagram.com/epamsystems
- Address: 10900 NE 8th St, Suite 1680, Bellevue, WA 98004
- Phone: +1 267 759 9000
5. Seattle Software Developers
Seattle Software Developers builds financial apps for banking, payments, and money management. It integrates payment gateways and builds personal finance tools, trading platforms, and fraud detection systems. The company also offers general custom software development, cloud applications, and staff augmentation.
Its process runs from planning and architecture through development, launch, and ongoing improvements. Businesses can hire a dedicated team for a whole build or add developers to an existing project. It is a good match when the scope is one customer app, transaction workflow, or financial tool.
Key Facts
- Core services: Financial application development, custom software, and staff augmentation.
- Relevant capabilities: Payment integrations, personal finance tools, trading applications, and fraud detection.
- Delivery models: Full project delivery or support for an existing team.
- Market presence: Seattle area, Washington.
Contact Information
- Website: seattlesoftwaredevelopers.com
- E-mail: moc.srepolevederawtfoselttaes@olleh
- Facebook: www.facebook.com/people/Seattle-Software-Developers
- LinkedIn: www.linkedin.com/company/seattle-software-developers
- Instagram: www.instagram.com/seattle.software.developers
- Address: 4 102nd Ave NE, Bellevue, WA 98004
- Phone: (425) 307-9066
6. Globant
Globant's banking practice builds digital channels, integrates cloud services, and modernizes processes. Its published banking work includes a digital transformation project with Itaú and robotic process automation for IDB Bank.
For banks planning a wider digital program, Globant pairs application development with customer experience and workflow improvements. It builds prototypes as well as larger implementations, including web applications and AI-supported processes. Institutions that want new customer-facing services and changes to the operations behind them can do both with Globant.
Key Facts
- Core services: Digital banking channels, cloud integration, process automation, and software implementation.
- Published banking projects: Itaú and IDB Bank.
- Project fit: Banking experiences connected with operational modernization.
- Location: Seattle, Washington.
Contact Information
- Website: www.globant.com
- E-mail: moc.tnabolg@ih
- Facebook: www.facebook.com/Globant
- Twitter: x.com/globant
- LinkedIn: www.linkedin.com/company/globant
- Address: 1601 5th Avenue, #603, WA 98101, Seattle
- Phone: +1 786-841-1898
7. AccelOne
AccelOne works from Kirkland, Washington, and Buenos Aires, Argentina, with staff across the United States and Latin America. Its financial projects include a cryptocurrency reconciliation engine for Xapo, a credit empowerment platform, and a decentralized lending platform.
The company handles product design, software engineering, modernization, testing, deployment, and support. Clients can choose full product delivery or staff augmentation. AccelOne fits financial projects involving transaction reconciliation, digital wallets, lending features, or integrations. Its past projects give buyers concrete examples to compare against their own banking software needs.
Key Facts
- Core services: Product design, software engineering, modernization, testing, and support.
- Financial project experience: Reconciliation, digital wallets, credit platforms, and decentralized lending.
- Delivery models: Full product delivery and US or nearshore staff augmentation.
- Location: Kirkland, Washington, and Buenos Aires, Argentina.
Contact Information
- Website: www.accelone.com
- E-mail: moc.enolecca@ofni
- LinkedIn: www.linkedin.com/company/accelone
- Address: 608 State St, Kirkland, WA 98033
- Phone: +1 (800) 863-6814
8. Zazz
Zazz builds fintech apps with mobile banking, digital wallets, payments, and account management. Its services cover interface design, custom development, integration, QA, deployment, and maintenance.
Its financial apps include balance views, transaction histories, statements, payment transfers, and user authentication. Zazz also builds cross-platform apps with React Native and Flutter. Banking and fintech teams focused on a mobile product can use it to run the same app on many devices and connect it to external financial services.
Key Facts
- Core services: Fintech app development, UI/UX design, integration, QA, and maintenance.
- Relevant functionality: Mobile banking, digital wallets, payments, and account management.
- Technologies: React Native and Flutter for cross-platform applications.
- Location: Bellevue, Washington.
Contact Information
- Website: www.zazz.io
- Facebook: www.facebook.com/Zazz.Official
- Twitter: x.com/Zazz_Official
- LinkedIn: www.linkedin.com/company/zazz-io
- Instagram: www.instagram.com/zazz.io
- Address: 2018 156th Ave NE, Bldg F #100, Bellevue, WA 98007
Conclusion
Washington businesses have a range of banking software development partners, from local engineering teams to large international consultancies and remote fintech specialists. The companies in this list cover different needs, including mobile banking, payment systems, API integration, cloud modernization, data engineering, financial applications, and digital transformation. The right choice depends on the project's technical scope, financial domain, delivery model, and need for local collaboration. Reviewing relevant project experience, services, technologies, and engagement models can help narrow the shortlist to a partner that matches the bank's specific software requirements.