Top C# Development Companies in London
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Explore Reviewed C# Development Companies in London — Find Skilled C# Developers for Your Project
Certain agencies may be featured through sponsored placements. Rankings and SF Scores remain unbiased and are based solely on our evaluation methodology.
21 Companies
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SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Engineering peace of mind
Vention is a global software development company with over 20 years of experience delivering innovative, scalable solutions for startups and large enterprises. We handle projects of any size and complexity, enabling clients to accelerate growth, launch new products, and seize emerging opportunities. With a global network of 3,000+ experienced developers, we provide top engineering talent aligned to your time zone, technology stack, and business goals. We’ve partnered with 500+ industry-leading organizations, including PayPal, IBM, Mount Sinai, PwC, and Postman, contributing to more than $15B in client acquisitions. Our engagement model helps companies reduce operational costs by up to $600K annually, while our long-term relationships—averaging over 36 months and extending up to 16 years—reflect strong client trust and satisfaction. Vention offers full-cycle software development services, from strategy and architecture to deployment and optimization. Our capabilities include custom software development, web and mobile app development, QA and testing, cloud and DevOps, eCommerce platforms, AR/VR experiences, artificial intelligence, and blockchain solutions. As a trusted technology partner, Vention empowers businesses to innovate faster, scale efficiently, and stay competitive in an evolving digital landscape.
See all 9+ PortfoliosUndisclosed/hr
$25,000+
1,000 - 3,000
London, UK
Verified Client Review
Mobile App Dev for Sports Tracking Platform
Reviewed by: Brent Varrall, Founder at AllGains View all 16 Reviews54
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Software Engineering Laboratory
SENLA is a fast-growing software development company with a proven track record and 5 EU locations. Our team of 700+ certified technical specialists and managers has large expertise in a full-cycle development from BA to maintenance as well as separate services like QA or UX Audit. For more than 10 years of operation we have successfully completed over 350 projects in FinTech, Healthcare, Manufacturing and other industries. Careful quality control, timely delivery and lifetime warranty have helped us win the loyalty of almost 90% of our clients who have decided to cooperate with us on a regular basis. Services: - custom software development - Web/mobile app development - IT staff augmentation - UX/UI Design - CRM consulting and SI - enterprise app modernization - BI& Big data consulting &SI Get in touch with us and scale your business fast and effortlessly
See all 31+ Portfolios$25-$49/hr
$10,000+
500 - 1,000
London, UK
Verified Client Review
Staff Aug & Data Platform Dev for Agriculture Solutions Co
Reviewed by: Brian Faison, Business Controller at YARA GmbH & Co. KG View all 5 Reviews41
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
De[coding] Capabilities
Ezulix is a custom AI software development company specializing in engineering hyperautomation solutions across all business industries. Certified as a CMMI Level 5 IT company, Ezulix caters to the digital transformation and overall IT operations needs of enterprises, startups, SMBs, and large corporations. It uses a consulting-first approach and carefully analyzes the existing workflows of a business, strategizes a step-by-step automation roadmap, and curates an AI-powered business process automation solution for businesses, helping businesses reduce manual workload at speed and scale with intelligent workflows. In addition to business software solutions, Ezulix also specializes in first-of-its-kind mobile app development. It fulfils unique app development requirements with dedicated app development teams.
View Ezulix Software ProfileUndisclosed/hr
$7,000+
50 - 100
London, UK
Verified Client Review
Mobile App & Web Revamp & Maintenace for Car Manufacturer
Reviewed by: Bob Laishley, CEO at Caterham View all 8 Reviews41
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Let's Build Our Future, Together
Vivasoft Limited is a leading software company in Bangladesh, certified under ISO 27001:2022 and ISO 9001:2015, as well as GDPR-compliant that helps global businesses build scalable, secure, and high-performing digital products. Since 2016, the company has offered custom software development, IT staff augmentation, AI development, and mobile app development through a team of 300+ skilled engineers with expertise in JavaScript, Python, C++, C#, .NET, Java, PHP, Golang, and Flutter. Trusted by global brands such as Azerion, klikit, Numberskills, Stickler, Goava, Dunite, Wellteam, Hink, and Iceberg, Vivasoft has delivered 80+ projects across retail, telecom, finance, healthcare, sports, manufacturing, education, and e-commerce. Serving clients in the Netherlands, Sweden, Singapore, Malaysia, Australia, and the USA, Vivasoft gives businesses access to the top 1% of tech talent to turn their ideas into powerful digital products.
See all 2+ Portfolios$25-$49/hr
$10,000 - $100,000
250 - 1,000
London, UK
38
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
High performance dedicated teams globally
We create specialised software development teams that grow businesses' technological proficiency. We collaborate with the top engineers in Eastern Europe to help you produce high-quality software more quickly than anybody else. All of our clients, who manage medium-sized to large-sized businesses in the US, Canada, Switzerland, Germany, the Netherlands, and ten other European nations, are willing to suggest Crunch-IS as a reliable development partner.
View Crunch-IS Profile$25-$49/hr
$10,000+
50 - 249
London, UK
Verified Client Review
React Native Staff Augmentation for Technology Consulting Company
Reviewed by: Bob Visnov, CEO at Timegen Consulting View all 4 Reviews38
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Unique teams for unique companies
MWDN is a global all-in-one hiring service provider bridging the talent gap with top 5% experts across different time zones for companies of any size and stage in Israel, Europe, the USA, and Canada. We provide IT outstaffing, recruitment (headhunting) and flexible models like outstuff-to-hire for our partners already 23 years. We also customize our services for each client, and some of them have stayed with us for 17 years! Clients confidently rely on MWDN to hire or build teams in such industries as cybersecurity, healthcare, fintech, blockchain, logistics and 10 more. What we offer: ? Unlimited talent access worldwide and 200K+ vetted experts across every major tech stack, ready when you are ? The first 4–5 pre-qualified candidates within 1 week ? $6–7K saving per hire monthly on direct labor costs and other payment plans for tight-budget projects ? 23 years of expertise in 15 industries ? Full-cycle support: from headhunting to HR, payroll, legal & retention — everything an in-house team provides ? Risk-free collaboration: trial period and guaranteed replacement included We are about proven reliability: 23 years in business, 96% referral rate, 4.9/5 client satisfaction and global trust: 400 clients worldwide across 4 continents.
View MWDN Profile$25-$49/hr
$25,000+
140 - 170
London, UK
38
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Enterprise-grade software solutions for small and medium businesses
Red Eagle Tech is a London-based technology partner helping SMEs get more from their systems without wasting time on tasks that can be automated or streamlined. We’re security-first, practical, and straight-talking, focused on making your tech feel calm, reliable, and fit for purpose, whether you need ongoing support or a bigger step-change. Our services cover managed IT operations (support, monitoring, security, cloud and device management) alongside bespoke software and automation. We also build tailored web apps and integrations, using data and AI where it genuinely adds value, so teams can move faster, reduce manual work, and make better decisions.
View Red Eagle Tech Profile$150-$199/hr
$1,000+
5+
London, UK
37
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Scale your business with world-class software
Scrums.com is the world’s 1st Software Engineering Orchestration Platform (SEOP) to help teams build faster, smarter, and at scale. We combine human expertise, AI-powered agents, and actionable software analytics into one flexible platform that orchestrates every aspect of software engineering. Whether you need to augment your team, spin up a dedicated development squad, or boost delivery with autonomous AI agents, Scrums.com gives you the control and scalability to move faster - and smarter. From startups to global enterprises, 400+ global companies trust Scrums.com to streamline engineering workflows, unlock talent from Africa’s top software minds, and drive performance through intelligent automation and insight. With presence in Johannesburg, Cape Town, Nairobi, Lagos, London, and New York, we’re building the future of software engineering - seamlessly orchestrated, insight-driven, and globally powered.
View Scrums.com (formerly SovTech) Profile$50-$99/hr
$55,000 - $100,000
250 - 300
London, UK
Verified Client Review
Mobile App Dev for Digital Solutions & Consulting Company
Reviewed by: Asen Bahtev, Co-Founder at MNDB LLC View all 3 Reviews33
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Salesforce development and implementation consulting partner
Innovadel Technologies is a leading provider of innovative IT solutions, specializing in Salesforce implementation, integration, and support. We empower businesses across diverse sectors with cutting-edge technologies to drive digital transformation and achieve their strategic goals. Our comprehensive service offerings extend beyond Salesforce, encompassing Shopify, WordPress, BigCommerce, software development, custom application development, mobile app development, web development, Cloud Consulting, Data Analytics, and AI/ML Solutions. We are committed to delivering high-quality solutions, exceeding client expectations, and building long-term partnerships. Our deep industry expertise, focus on leveraging the latest technologies, results-oriented approach, and unwavering commitment to customer satisfaction set us apart.
See all 3+ Portfolios$50-$99/hr
$10,000 - $15,000
50 - 60
London, UK
29
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Generative AI Development and Consulting Company
ARCQ AI is a London-based consultancy specializing in generative AI software development and AI consulting services. We provide tailored AI solutions including machine learning, natural language processing, computer vision, and chatbot development to help businesses automate processes, gain insights, and enhance customer engagement.
View ARCQ AI Profile$100-$149/hr
$25,000 - $50,000
1 - 9
London, UK
29
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
AI is embedded in everything we do!
A Global AI-Powered Technology Partner helping Businesses Grow and Scale through End-to-End Digital Transformation. We partner with leading enterprises to drive revenue growth and solve complex, industry-specific challenges. Our software services encompass the full cycle of software development, from ideation to delivery to security and maintenance - our globally distributed team of expert talent is equipped to deliver future-ready solutions & proven results. ? Strategy Innovation: Creating transformational digital products (mobile & web) that combine customer experience, market opportunity, and emerging technology. Augmentation: Empowering your team with the technical talent and skills needed to accelerate development and build high-quality digital products - software development, QA/testing, data analytics, UX/UI, and product management. Modernization: Re-architecting legacy technology for better speed, scale, security, and user experience. Digitalization: Building intelligent digital solutions that automate manual and inefficient processes. ? Expertise Artificial Intelligence New Product Innovation Agile Development & QA Testing Enterprise Platform Implementation Strategy & Business Consulting Data & Security ? Artificial Intelligence Generative AI (Gen AI) Custom Models Data Science Machine Learning (ML) Computer Vision MLOps Large Language Learning (LLM) Natural Language Processing (NLP) ? Solutions Software Development (Web, Mobile, Data, Cloud) AI/ML Transformation User Experience (UX/UI) Data Analytics & Migration Quality Assurance Security & Compliance DevOps & SecOps QA Testing & Automation Business Process Automation Platform Integration (Salesforce, AWS, GCP, Azure, ServiceNow, Databricks, Appian, Microsoft and more) AI Platform Integration (Meta, Open AI, Google AI, Mistral AI, Dall.E, ultralytics, stability.ai, Langchain, LlamaIndex, Pinecone, Hugging Face and more)
View 10Pearls Profile$25-$49/hr
$50,000+
1,000 - 2,000
London, UK
29
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
We build products and teams that help companies grow
Four Ages offers complete software development solutions that are customized to meet the diverse business needs and technological objectives of its clients, ranging in complexity. Tech stack: > Back-end - JavaScript, PHP, Python, Java, Ruby on Rails, C/C++, .Net, Node JS > Front-end - React JS, Angular, Vue > Mobile - iOS, Android, Flutter, React Native > Databases - MongoDB, PostgreSQL, MySql, AWS DynamoDB, Firebase, Couchbase > Cloud - AWS, MS Azure, GCP
View Four Ages Software Profile$25-$49/hr
$50,000+
10 - 49
London, UK
Verified Client Review
IT Consulting & Custom Software Dev for Ticketing Co
Reviewed by: Riley Allen, Product Owner at Ticketing Co View all 5 Reviews28
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
ON DEMANDS SOFTWARE TEAMS
We are a highly experienced and qualified team of professionals with a proven track record of delivering quality software solutions to clients. Here are a few reasons to choose us: 675+ software developers Expertise in different technologies Strong reputation for quality work Experience working on complex projects for different industry verticals ????At ValueCoders, we offer cutting-edge software solutions tailored to meet the unique needs of your business. Our goal is to empower businesses of all sizes with innovative technologies that streamline operations, deliver exceptional results, and drive growth.
View ValueCoders (UK) Profile$300 </hr
$1,000 - $10,000
500 - 1,000
London, UK
27
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Creating Beautiful Designs & Wesbites
So-Creative is an award winning web design and development agency based in London. With a reputation for redefining digital experiences, they craft bespoke websites and cutting-edge software solutions that captivate audiences and deliver results. Their talented team combines creativity, collaboration, and advanced technology to help businesses develop memorable brands, generate leads, and achieve lasting success online. By offering streamlined, cost-effective processes, So-Creative is the trusted partner for businesses seeking to transform their digital presence and unlock growth through innovative design and technology.
View So-Creative ProfileN/A
$50+
11 - 50
London, UK
26
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
UDEVHUB
Our global software development company offers custom engineering solutions, based in Ukraine, with representative offices in various countries, including the USA, UK, Germany, Israel, Canada, Australia, and UAE.
View UDEV HUB Profile$25-$49/hr
$25,000+
250 - 999
London, UK
Verified Client Review
IT Staff Augmentation for Medical Device Manufacturer
Reviewed by: Artem Malynovski, Co-Founder & CTO at Mawi Solutions View all 3 Reviews26
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
A CMMi Level 3 Company
It is one of the leading firms for providing solutions and services to Web Application Development. It utilizes technology to convert a vision into reality on web and mobile. The skilled developers are scalable and flexible to fulfill client requirements. It has a global reputation for delivering creative websites and mobile applications within time and budget. The goal is to combine quality web design development with offshore gains, to give online solutions and considering the latest economic downtrend issues away from clients. Whether you are a small-sized company looking to set up in the market, or a huge enterprise waiting for expansion, they can consider numerous solutions to guide in achieving the targets.
View Dotsquares Profile$25-$49/hr
$5,000+
250 - 999
London, UK
Verified Client Review
CRM Consulting & Digital Marketing for Energy Company
Reviewed by: Mitchell Thomas, Operations Manager at Think Renewable View all 4 Reviews24
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
We create web and mobile apps that stand out.
Based in Maribor, Slovenia, and London, UK, Equaleyes Solutions is a multi-award-winning software development firm. In addition to developing, managing, and maintaining web platforms with millions of monthly users, we also create mobile digital products. Equaleyes has a clear understanding of the situation: You want a development partner who will take the time and money to truly consider your project and assist you reach your product goals. Equaleyes will provide your vision with the passion, commitment, and attention it need to reach its full potential if it is one of boldness, loyalty, and greatness.
View Equaleyes Solutions Ltd. Profile$50-$99/hr
$1,000+
10 - 49
London, UK
Verified Client Review
Used them for multiple projects - always deliver
Reviewed by: Zoe Peden, Founder at Iris Speaks View all 2 Reviews19
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Designing. Building. Delivering
High Digital is a Cyber Essentials certified and ISO/IEC 27001 accredited data product developer. We design, build, and deliver data products. We adopt a collaborative and agile approach to cover all areas from product planning and design to UI/UX, development, delivery, and support. We have significant experience building Martech, SaaS, ESG, analytics, Bi, and logistics data products.
View High Digital Limited ProfileN/A
$5,000+
10 - 49
London, UK
19
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
You Dream IT - We Dev IT
DEVITGROUP LTD is a UK-registered software engineering company specializing in AI integration, scalable SaaS development, and enterprise .NET modernization. We partner with startups, scaleups, and established organizations to design and deliver production-ready digital platforms—from MVP SaaS products to complex, enterprise-grade systems. Our expertise centers on modern .NET backend architecture, cloud-native infrastructure, and AI-powered feature development that drives measurable business value. We help companies enhance existing products or build new platforms with intelligent automation, advanced analytics, and seamless system integrations. Core services include AI feature integration for SaaS applications, custom SaaS product development, legacy .NET system modernization, cloud migration, API architecture, and performance optimization for high-traffic environments. We prioritize secure coding practices, scalable infrastructure design, and long-term maintainability to reduce operational risk and support sustainable growth. Our engineering approach is grounded in clean architecture principles, DevOps automation, CI/CD pipelines, and transparent communication. By combining technical excellence with structured delivery processes, DEVITGROUP LTD ensures predictable timelines, optimized performance, and scalable technology foundations for ambitious businesses.
View DEVITGROUP LTD Profile$25-$49/hr
$25,000+
10 - 49
London, UK
18
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Boost Your Business with Custom Software Solutions
KnubiSoft: Your Premier B2B Technology Solutions Partner KnubiSoft stands out as a comprehensive technology solutions provider, specializing in creating exceptional software and innovative products tailored to meet your business needs. Our expertise spans the entire project lifecycle, including custom software development, team augmentation, intuitive UI/UX design, and rigorous QA testing. With a highly skilled team ready to elevate businesses of all sizes, we provide invaluable insights and technical proficiency. We cater to a wide array of industries, including Financial Services, Healthcare, E-Commerce, Logistics, and more. Our diverse knowledge base means that we can seamlessly integrate solutions across various sectors. Utilizing leading-edge technologies such as HTML/CSS, React, Java, Python, and Swift, KnubiSoft ensures that each deliverable is crafted to meet the unique demands of our clients. Our specialized services include end-to-end custom software development, legacy system support, cloud migration, and team augmentation to help organizations scale efficiently. Moreover, our proprietary product, Testlum, revolutionizes the QA process through automated testing, enhancing overall product quality while optimizing budgets. Trust KnubiSoft for standout technology solutions that drive growth and innovation in your organization.
View KnubiSoft Profile$25-$49/hr
$25,000+
50 - 249
London, UK
17
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Powering Your Ambition
Niteco, which was founded in 2010 by Swedish tech veteran Pelle Niklasson, has completed hundreds of projects for clients in over 30 nations. We have more than 300 professionals with a variety of backgrounds and specialties. Niteco is a strong believer in the value of a supportive community, a welcoming workplace, and the special fulfillment that comes from carrying out good deeds.
View Niteco Profile$50-$99/hr
$10,000+
250 - 999
London, UK
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