Top 13 .NET Development Companies In The U.S. (2025)

Finding the right .NET development company is not easy—especially when a quick Google search for “.NET development companies in the US” returns millions of results. Narrowing down the options can be a long, tedious process, and it’s often hard to know which company will truly deliver the performance, scalability, and reliability your project demands.

But look no further… We’ve compiled a list of the top 13 .NET development companies in the US to help you find the perfect partner for building high-quality, enterprise-grade applications.

What Makes a Top .NET Development Company?

Before diving into the list, it’s important to define what separates the best from the rest. Many firms promise cutting-edge solutions, but not all deliver. Here are the key criteria we used when evaluating our selections:

• Proven Case Studies – Review the company’s track record by looking at past .NET projects. Go beyond the surface to understand the architecture, performance, and scalability of the applications they’ve delivered.
• Technical Proficiency in the .NET Ecosystem – A top .NET development team should demonstrate deep expertise in the full Microsoft stack—covering ASP.NET, .NET Core, Azure integration, API development, and more. They must also follow best practices for security, performance optimization, and maintainability.
• Industry Experience – Companies that have built solutions for your industry will better understand your workflows, compliance requirements, and end-user needs—resulting in faster delivery and better-aligned functionality.

Top .NET Development Companies in the U.S.

1. 6B

At 6B we specialise in .NET development, creating robust, secure, and high-performance bespoke software using Microsoft’s powerful framework. Our expertise covers everything from greenfield application builds and legacy system re-engineering to seamless integration with Azure, Active Directory, SQL Server, and third-party APIs. By leveraging technologies such as ASP.NET Core, Entity Framework, and .NET Core, we deliver modular, enterprise-grade solutions that prioritise maintainability, testability, and scalability.

Our approach is collaborative and agile, starting with a discovery phase to understand your objectives and system environment before architecting and delivering a tailored .NET application. We work across diverse sectors including finance, energy, logistics, and the public sector, where high data demands, complex business logic, and compliance requirements are key. Alongside our UK base, we place a strong focus on supporting clients in the USA, ensuring our solutions meet international standards and deliver value across borders. Beyond development, we provide ongoing maintenance, optimisation, and enhancement services to ensure your .NET applications remain reliable, performant, and aligned with evolving business goals.

Our .NET development expertise includes:

• Bespoke application design and build using ASP.NET Core and .NET Core
• Modernisation and re-engineering of legacy systems
• Seamless integration with Azure, Active Directory, SQL Server, and third-party APIs
• Enterprise-grade architecture for scalability, security, and performance
• Agile, collaborative delivery tailored to your business goals
• Ongoing maintenance, optimisation, and feature enhancements

If you’re looking for a .NET development company that delivers results – click the button below to get in touch. Or, if you’d like to learn more about our .NET development services, then check out our service page here.

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2. Leobit

Leobit stands out as a full-cycle software development company with deep expertise in the .NET ecosystem, having delivered over 100 .NET projects since its inception in 2014. They boast a team of 78 Microsoft-certified engineers and a Microsoft Solutions Partner designation, showcasing their proficiency in building scalable, secure enterprise applications using ASP.NET, .NET Core, Azure, Blazor, .NET MAUI, microservices, and modern architectural patterns.

Though their primary development centre is in Lviv, Ukraine, Leobit maintains a representative office in Austin, Texas, to support clients throughout the USA.

3. BairesDev

BairesDev is a seasoned provider of .NET development services, trusted by more than 500 clients since 2009. Their .NET specialists—drawn from the top 1% of talent with an average of over 10 years’ experience—have delivered in excess of 100 tailored .NET projects. These span custom software, integration and API development, migration and modernisation, e-commerce platforms, enterprise solutions, and cloud-based systems utilising frameworks such as ASP.NET, ASP.NET Core, Entity Framework, and Azure services.

Operating globally, BairesDev also maintains a presence in the United States—offering staff augmentation, dedicated teams, and outsourcing solutions to bolster domestic development efforts with their elite .NET expertise.

4. Sigli

Sigli is a forward-thinking software development firm delivering full-cycle digital transformation and product development services. Their web development offering explicitly includes .NET, alongside JavaScript, React, and Angular, demonstrating their ability to build robust, scalable web solutions using Microsoft’s ecosystem. They are frequently engaged for .NET backend work in projects such as portals and system modernisations.

While Sigli’s main offices are based in Antwerp, Vilnius, and London, they also collaborate with clients across the USA, supporting projects that require their .NET expertise in international contexts.

5. Plavno

Plavno offers high-quality .NET development services, providing access to the top 3 percent of the industry’s developers. Their capabilities span crafting custom .NET applications, migrating legacy systems to ASP .NET Core, building enterprise solutions (like ERPs, CRMs, BI tools), developing scalable cloud-based systems via microservices, and designing seamless integrations and APIs using technologies including Entity Framework, ASP .NET Web API, WCF, and vendor SDKs.

With over 15 years of experience and more than 300 projects delivered, Plavno’s expertise is underpinned by a strong foundation in offshore and nearshore software development. While they maintain headquarters in Poland, Kazakhstan, and the UK, their .NET services are structured to support clients across the USA and beyond.

6. Blackthorn Vision

Blackthorn Vision is a seasoned software development firm deeply skilled in the .NET ecosystem. As a Microsoft-partnered company, they specialise in crafting custom .NET solutions—from sleek web and enterprise applications to API integration, modernisation of legacy systems, scalable e-commerce platforms, and cloud-native applications. Their team supports the full development process, including architecture design, consulting, testing, deployment, and ongoing post-launch maintenance.

Although headquartered in Lviv and Wrocław, Blackthorn Vision maintains a global client base that includes businesses in the United States and beyond. Their English-speaking engineers, flexible engagement models, and strategic timezone coverage ensure smooth collaboration and access to top-tier .NET development support across borders.

7. ScienceSoft

ScienceSoft is highly experienced in .NET development, having successfully delivered over 230 large-scale .NET projects. As a Microsoft Partner since 2008, they offer end-to-end services including design, implementation, testing, integration, modernisation, and ongoing support—spanning ASP.NET, .NET Core, Xamarin, desktop and mobile applications, cloud migrations, microservices and API development. Their team includes more than 60 .NET developers, backed by a full-scale project management office, and they pride themselves on quality practices underpinned by ISO-certified processes.

While their development centre spans multiple global locations, they also maintain a presence in the United States, including a scheduled office in the Dallas area of Texas—facilitating smooth collaboration for U.S.-based clients seeking .NET software solutions.

8. Instinctools

Instinctools brings over 25 years of focused experience in .NET application development, supporting projects from conception through post-launch support. Their services span consulting, microservices architecture, API development and integration, migration and upgrading, quality assurance, maintenance, multi-platform UI through .NET MAUI, Xamarin, and Blazor, as well as containerisation for cloud readiness.

While headquartered in Europe with locations in Germany and Poland, they also maintain an office in Potomac, Maryland (USA), underscoring their readiness to collaborate with American clients seeking premium .NET expertise across time zones.

9. Sky Net Technologies

Skynet Technologies is a seasoned .NET development company offering flexible and fully tailored .NET solutions that seamlessly align with diverse business objectives. Their skilled developers deliver scalable, secure applications across web, desktop, and enterprise environments—leveraging a breadth of Microsoft technologies including C#, ASP.NET, MVC, MVVM, WCF, WPF, Web API (up to version 2.0), and support for framework versions 2.0 through 4.6.1—all structured to ensure robustness and long-term maintainability.

With over 23 years of experience, Skynet serves businesses of all sizes across the USA, spanning cities from Las Vegas and Los Angeles to Miami and New York. This extensive U.S. coverage underscores their capability to effectively partner with American clients by offering both technical excellence and geographically distributed support.

10. iFour

iFour is a Microsoft-certified .NET development company delivering custom, secure, and scalable web, desktop, mobile, and cloud applications. Their seasoned team employs MVC.NET, ASP .NET Core, Blazor, WPF, Xamarin, API development, CMS, modernisation of legacy systems, Azure cloud services, and more—backed by Agile processes and strong emphasis on quality and security.

Although their headquarters are based elsewhere, iFour maintains a U.S. office in Indiana, facilitating seamless collaboration with American clients and underscoring their global reach in delivering .NET solutions.

11. Avidclan Technologies

Avidclan Technologies positions itself as a premier .NET development company, delivering robust, scalable, and bespoke solutions across web, desktop, and cloud platforms. Their services span the full development lifecycle—including custom .NET application development, .NET Core implementations, enterprise-level software, migration and integration of legacy systems, and seasoned consultancy aimed at performance, security, and alignment with business objectives.

Headquartered in India, Avidclan also maintains a U.S. office in Sterling, Virginia, reflecting their commitment to serving American clients with responsive, time-zone-aware collaboration and expert .NET delivery.

12. The One Technologies

The One Technologies operates as a specialist .NET development agency based in California, offering pre-vetted ASP.NET developers available through a flexible, risk-free 15-day trial. They support the full development lifecycle—from consultation and architecture design to coding, quality assurance, deployment, and post-launch maintenance. Their offerings include bespoke web, mobile, and enterprise software, migration and upgrades, API integration, and Agile-based team extensions.

With over a decade of experience, a team exceeding 120 .NET experts, and more than 750 successful projects, the company positions itself as a budget-conscious yet highly capable partner for US businesses—particularly those in Silicon Valley—seeking secure, scalable, and responsive .NET solutions.

13. TechnoBrains

TechnoBrains delivers tailored ASP.NET development services, offering robust, scalable, and secure applications using a comprehensive range of Microsoft technologies—from ASP.NET MVC, .NET Core, WCF, WebForms, Razor, Entity Framework, C#, and Web API to desktop frameworks like WPF, WinForms, XAML, and legacy tools such as Silverlight. Their full-stack approach also covers cloud deployment (Azure, AWS, Google Cloud), testing frameworks, build automation, and Agile methodologies to ensure quality and performance.

Although headquartered in India, TechnoBrains extends its reach into the United States, with a presence in San Francisco, California, providing American clients with accessible, time-zone-aligned collaboration and dependable .NET delivery.

Why Hire One of the Best .NET Development Companies in the U.S.?

When you’re building a robust, scalable, and secure application, the quality of your development partner can determine the success of your entire project. The leading .NET development companies in the U.S. bring more than just technical skills—they combine strategic thinking, deep platform expertise, and industry-specific insight to ensure your application not only works, but excels.

A top-tier .NET firm delivers proven quality and reliability, following rigorous development standards and thorough testing to ensure your solution performs flawlessly under real-world conditions. Their teams are fluent across the Microsoft ecosystem, from ASP.NET MVC and .NET Core to Azure cloud integration and complex API architecture, giving you access to specialists who can address advanced requirements with ease.

By working with the best, you also benefit from faster time-to-market. These companies know how to streamline workflows, avoid unnecessary rework, and leverage reusable components to accelerate delivery without sacrificing quality. They also think beyond the immediate project, building solutions designed for long-term growth—applications that can scale with your business, adapt to emerging technologies, and remain easy to maintain over time.

Equally important, the best .NET companies understand your industry. Their experience allows them to anticipate challenges, meet regulatory demands, and design solutions that align perfectly with your market’s needs. Ultimately, hiring one of the top firms isn’t just about getting a great application—it’s about gaining a trusted technology partner who can evolve with you and keep you competitive in an ever-changing digital landscape.

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