Top Fintech Custom Software Development UK

Fintech in the UK is more than a buzzword. Over the past decade, the sector has pushed traditional finance to rethink how services are built, delivered, and scaled. At the heart of this shift is custom software development, where teams design platforms that handle everything from digital payments to regulatory compliance. Instead of relying on off-the-shelf systems, businesses are turning to tailored solutions that match their workflows and market goals. It’s not just about efficiency; it’s about keeping pace with an industry that never really stands still.

In the sections below, we’ll highlight the top software development companies in the UK that specialize in building custom fintech solutions. These firms bring different strengths to the table – from rapid product launches to large-scale, compliance-heavy projects – giving businesses the flexibility to choose a partner aligned with their growth stage and vision.

1. Lengreo

LENGREO works at the intersection of marketing and technology, supporting companies that need more than a standard approach to growth. Our projects often start with analysis and research so that any strategy or product development is grounded in real business needs. From there, we combine digital marketing, SEO, and outreach with technical capabilities like web and mobile app development. The idea is not to deliver one-off tasks but to align our work with how a business actually operates.

Alongside marketing strategy, we cover practical areas like website creation, campaign management, and lead generation. Many of our projects involve helping clients build a consistent digital presence while also finding measurable ways to connect with their target audience. Because we work across different industries, we adapt methods to fit each case instead of relying on pre-set solutions. That mix of consulting and hands-on execution lets us stay involved throughout the process, from planning to follow-up support.

Key Highlights:

Emphasis on mapping real financial workflows before development
Integration with compliance and regulatory requirements
Continuous involvement across design, testing, and rollout
Experience in tailoring tools to specific fintech needs

Services:

Custom fintech software development
Mobile and web app development
System integration with existing finance platforms
Ongoing support and optimization

Contact Information:

Website: Lengreo
Contact Email: hi@Lengreo.com
Phone Number: +31 686 147 566
LinkedIn: Lengreo
Twitter: @Lengreo
Instagram: @Lengreo

Our cases

SEO for BIM & VDC Services Provider

PPC For Adult Content Platform

Biological Age Blood Testing Kit

2. Influential Software

Influential Software focuses on building .NET platforms for financial institutions that need scalable and secure systems. Their work often involves modernising legacy applications, such as replacing old mainframes with modular .NET Core microservices. By integrating with payment providers, KYC checks, and CRM tools, they help financial firms shift from rigid setups to more flexible environments that can handle new customer expectations and regulatory demands.

They also pay attention to how users interact with financial products day to day. Projects have included creating mobile-first banking portals and digitising workflows for brokers and advisory platforms. The aim is usually to improve efficiency without interrupting core operations, while still meeting FCA and GDPR requirements. Over time, their solutions are designed to scale across new regions and adapt to evolving compliance standards.