Top C# Development Companies in Illinois
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Explore Reviewed C# Development Companies in Illinois — 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.
20 Companies
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Illinois
0.0 (0 Reviews)
41
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
41
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Your Technology Partner
CodingCops is a full-cycle technology partner that helps businesses design, build, scale, and maintain software systems with confidence. We work with startups, growing companies, and enterprises to solve complex engineering challenges across custom software development, AI & machine learning, cloud & DevOps, and dedicated engineering teams. Our approach goes beyond traditional staffing or outsourcing. We operate as a long-term technology partner, embedding closely with our clients to understand their business objectives, technical constraints, and growth roadmap. From early architecture decisions to production-grade delivery, we focus on building systems that scale reliably, remain maintainable, and deliver measurable business outcomes. CodingCops is known for its elite engineering culture. Our developers are carefully vetted for technical depth, communication skills, and ownership mindset, ensuring consistent quality across every engagement. Whether clients need a fully managed solution or a dedicated team that integrates seamlessly with their in-house engineers, our teams contribute from day one. We work across industries including SaaS, fintech, healthcare, e-commerce, logistics, and enterprise platforms, supporting everything from MVP development to large-scale digital transformation initiatives. Our teams specialize in modern tech stacks such as AI/ML, Python, React, Node.js, Ruby on Rails, cloud-native architectures, and DevOps automation. At CodingCops, we don’t just deliver code. We help organizations reduce delivery risk, make better technical decisions, and build technology foundations that support long-term growth.
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$25-$49/hr
$5,000+
300 - 400
Chicago, USA
4.9 (6 Reviews)
38
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
38
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
We're Digital Agency From The Windy City
Tekglide is an IT firm based in Chicago and Houston. We are one of the best web solutions company with a strong portfolio. Our professional web development services are renowned all across the word. We have a team of experts offering Magento development, Shopify development, WordPress development, and custom development. Quality is our utmost priority and we are available for consultancy 24/7. We make sure to provide our clients an excellent experience so they can flourish their businesses.
View Tekglide Profile
$50-$99/hr
$5,000 - $100,000
35 - 40
Chicago, USA
Verified Client Review
Web Design & Dev for Carbon Bike Repair Company
Reviewed by: Charlotte Herzenberg, CEO at Carbon Bike Specialists View all 6 Reviews
0.0 (0 Reviews)
34
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
34
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Custom Software That Works in the Real World
SoftDoes is a Kansas City–based custom software, mobile app, and AI development firm building software that works in the real world, not just in demos or pitch decks. Our role is to turn your complex ideas and operational pain points into production-ready platforms that teams can actually run, trust, and scale. Every system is designed to fit into existing workflows, support compliance and security requirements, and remain maintainable long after launch. Who partners best with SoftDoes? Technical Leaders who want solutions, not headcount You need experienced engineers who can own delivery without creating more oversight. You want clean integrations, scalable architecture, and fewer operational fires. We build internal platforms, modernize legacy systems, and deliver AI automation. Business Owners solving operational complexity Your business has outgrown off-the-shelf tools and manual processes. You want software that improves efficiency without disrupting operations. We build custom platforms, workflow automation, and reporting systems. Founders who want to see their vision become reality You need a partner who can turn ideas into production-ready software. You want clear guidance, realistic timelines, and software that scales. We build MVPs, core platforms, and customer-facing applications. We work with organizations across: Healthcare Finance Construction Education Energy Technology Compliance-driven industries Clients choose SoftDoes for senior-level thinking, clear communication, and delivery they do not have to manage day to day. We operate as a true extension of your team, owning technical decisions and execution so you can stay focused on the business. Book a free product call and speak with an expert today. Website: https://softdoes.com/ Email: info@softdoes.com Phone: 816-800-2121
See all 1+ Portfolios
$50-$99/hr
$5,000+
50+
Merriam, USA
5.0 (2 Reviews)
5.0 (2 Reviews)
33
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
33
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
For Big Kids and Daredevils
Slingshot is a U.S.-based software and app development company transforming ideas into fully functional digital products. Using a unique 4-step, user-focused process, our strategists, designers, and developers craft personalized web and mobile applications tailored to your business needs. Whether you’re a Fortune 500 enterprise optimizing workflows or a small business launching an app, Slingshot delivers scalable, innovative solutions while building lasting partnerships to guide your digital growth confidently into the future.
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$100-$149/hr
$50,000+
10 - 49
Louisville, USA
Verified Client Review
Application Design & Dev for Startup Company
Reviewed by: Roland Achenjang, Founder & CEO, C2 Keep View all 2 Reviews
4.8 (1 Reviews)
32
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
32
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Designing bright for the hype
We are a Brightlab team, an international company of terrific developers and talented designers.There are 60 people in our team: UI/UX designers, front-end developers, back-end developers, mobile developers, QA engineers, DevOps engineers, business analysts. Brightlab has been on the market for about 6 years and during this time we have been working both with small businesses and big enterprises. We are ready to implement ideas of any complexity across the whole stack of technologies. All our solutions contain the foundation for SEO optimization, Google analytics service, etc.
View Brightlab Profile
$25-$49/hr
$10,000+
50 - 100
Chicago, USA
Verified Client Review
Web Design and Development for Technology Platform
Reviewed by: Alex Monroe, Co-Founder at Hotcake Golf View all 1 Reviews
4.7 (10 Reviews)
4.7 (10 Reviews)
31
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
31
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
OUR QUALITY, YOUR SUCCESS!
We are a collection of realists, strategists, developers, perfectionists, and idealists. We create amazing apps and software. Our primary objective as a leading enterprise is providing clients worldwide with digital transformation services and solutions. With a strong track record of more than a decade in the IT industry, 9series' experience is valued, with countless man-hours devoted to delivering cutting-edge services and solutions. We have built more than 65 mobile applications, successfully served more than 500 clients, and are dispersed throughout countries such as Sweden, Norway, Ireland, Finland, the United Kingdom, Germany, France, Italy, South Africa, Ghana, Kenya, the United States, Canada, Australia, Singapore, Malaysia, Turkey, Egypt, Iran, and the United Arab Emirates, among others.
View 9series Profile
$25-$49/hr
$1,000+
50 - 249
Seattle, USA
Verified Client Review
Web App Dev for Property Rental SaaS Platform
Reviewed by: Angel Ramos, CEO at ACuadrado Corp. View all 10 Reviews
5.0 (5 Reviews)
30
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
30
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Do What You Do Best - Better
Atomic Object is a U.S.-based custom software development company focused on building high-impact digital products that drive measurable business results. Our expert team designs and develops new software, enhances existing applications, modernizes legacy systems, and integrates AI-driven capabilities. As an employee-owned firm with offices in Chicago, Ann Arbor, Grand Rapids, and Raleigh-Durham, we deliver collaborative, high-quality solutions tailored to each client’s strategic goals.
View Atomic Object Profile
$150-$199/hr
$25,000+
50 - 249
Grand Rapids, USA
Verified Client Review
Custom Software Development for Consulting Firm
Reviewed by: Richard Berens, Managing Director at Accenture View all 5 Reviews
0.0 (0 Reviews)
30
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
30
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Empowering Businesses through Innovative Software Solutions
At Codevision Technologies, we empower organizations to work smarter through innovative digital solutions tailored for modern business challenges. Headquartered in India with a global footprint, we are a trusted technology partner for businesses across the USA looking to streamline operations, enhance employee experience, and drive measurable results. With deep expertise in Microsoft SharePoint, Power Platform, AI automation, and custom enterprise application development, our team brings strategic thinking and technical excellence to every project
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$25-$49/hr
$50,000 - $59,998
30 - 48
Carol Stream, USA
0.0 (0 Reviews)
29
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
29
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Impero IT Services: Expert Software & Mobile App Development Company
Impero IT Services provides comprehensive development solutions and a range of software engineering services designed for business productivity, agility and scalability. We're globally trusted, award-winning developers with 10+ years of delivering innovation and excellence. Portfolio of our services meets the varying requirements of our diverse clients. Our strong dominance in app development and quality services empower us to deliver efficient and seamless solutions for every industry. We'd be really happy to help you achieve your goals.
View Impero IT Services Profile
$100-$149/hr
$100 - $150
150+
Westmont, USA
0.0 (0 Reviews)
29
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
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
Vienna, USA
4.9 (6 Reviews)
28
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
28
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Proven Web and Mobile Apps Development Agency
Web and mobile applications are created by Armia Systems, Inc. to power online enterprises. Since 2003, we have provided platform and product development assistance to numerous startups and tech firms. We have a captive development centre in India with more than 125 superstar developers, and our headquarters are in Chicago, Illinois. Value and quality are combined in this hybrid model.
View Armia Systems Profile
$25-$49/hr
$5,000+
50 - 249
Deerfield, USA
Verified Client Review
Mobile App Design & Development for Coffee Shop Discovery Co
Reviewed by: Jonathan McCoy, Founder at Baristi View all 6 Reviews
0.0 (0 Reviews)
28
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
28
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
digital agency in Chicago
You don’t just need a brand—you need a presence. At Design Henge, we craft bold, high-impact digital experiences that make your business unforgettable. We’re not just any digital agency in Chicago—we’re the one that makes brands impossible to ignore.
View Design Henge Profile
$100-$149/hr
$100 - $1,000
50 - 60
Chicago, USA
0.0 (0 Reviews)
28
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
28
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Transforming Ideas into Digital Realities
StudioKrew is a leading mobile app and Game development company based in India, USA, UK, UAE, & Canada, since 2013. Creating customer success strategies and implementing them into solutions is what we do at StudioKrew. With 12 years of experience in providing smart IT solutions, our social nerds have mastered the art of pushing boundaries to create customised mobility solutions and achieve success stories. Simultaneously with developing exciting products, we work on maintaining strong client relationships, which are crucial for carrying forward business legacies. The StudioKrew team has been a top hand-picked tech company globally across different time zones. We deliver quick projects while maintaining high-level designs and development aesthetics, catering to the needs of the demanding market. Do you have an idea? Feel free to consult with our managers to brainstorm possibilities and strategies to create a viable product before you sign in. Contact Us Now. Our service offerings include: Product strategy and definition Mobile Game Development Casual Game Development Game Designing Studio High Graphics 3D Designing and Animation UX/UI design Native Mobile App Development React Mobile App Development AR/VR App Development Web development Backend services AI, Machine learning and data science eCommerce Web and App Development Revit Development and Consultancy Some of the sectors we specialize in: Product strategy and definition UX/UI design Automobile Advertisements Entertainment Education Healthcare Banking Training and Assessments
View StudioKrew Profile
$25-$49/hr
$2,000 - $6,000
80 - 120
Chicago, USA
0.0 (0 Reviews)
20
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
20
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Let us help you build your software solutions from
Web apps, mobile apps, custom software development, ERP consulting, cloud storage solutions, business due diligence, robotic process automation, business process automation, and other b2b infrastructure solutions are just a few of the b2b services offered by Collinsville, Illinois-based Swip Systems. We can work with your firm to identify the best technological options to improve the effectiveness and efficiency of your daily operations. Swip Systems is your one-stop shop for all of your company's IT requirements; we can handle any problems your business may be having with technology.
View Swip Systems Profile
$200-$300/hr
$5,000+
10 - 49
Collinsville, USA
0.0 (0 Reviews)
0.0 (0 Reviews)
18
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
18
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Inspired by Creativity, Driven by Results.
PDT, an astronomy company, was established with a novel idea about how to generate new products. Our work, which is based on creativity, is counterbalanced by a thorough comprehension of your company, your clients' needs, and your markets' demands. This distinctive, process-driven strategy has fueled our expansion to a global company with more than 120 innovation specialists. In order to add value for Astronics Corporation and its clients in the consumer, medical, defense, and aerospace industries, we keep an eye on the newest developments in design and technology. Authorities including BusinessWeek, Fast Company, the Industrial Designers Society of America, the Consumer Electronics Association, and the Chicago Athenaeum Museum of Architecture and Design have honored PDT's research, design, and engineering teams with more than 100 prestigious industry awards.
View PDT Profile
$150-$199/hr
$25,000+
50 - 249
Lake Zurich, USA
0.0 (0 Reviews)
18
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
18
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
IT Solutions That Match Your Needs!
We serve two distinct regions: the United States and the Gulf Cooperation Council. NCIT Solutions' goal is to offer affordable, practical outsourcing solutions. We provide you with offshore services that are customized to meet your unique needs. Our affordable IT solutions give you a competitive advantage and produce noticeable outcomes. We can handle all of your IT demands because we work with a wide variety of systems, including Linux, UNIX, Solaris, Windows, iOS, and Android. Our software team's primary skills include software design and graphic design.
View NCIT Solutions Profile
N/A
$1,000+
10 - 49
McCook, USA
0.0 (0 Reviews)
0.0 (0 Reviews)
18
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
18
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Crafting technologies to move business.
As seasoned agency partners, we understand what it takes to develop incredible digital solutions that add value, produce tangible results, and support your company's ongoing success in this dynamic environment. We are committed to becoming the best team for you to fulfill the mission and goals we set out to achieve together, whether you are working on a major enterprise platform or a brand-new startup. "Do Good" is our motto. Be decent. It is a fundamental principle of our family-run firm that directs our daily efforts to deliver the finest possible service and the greatest possible output. We are honored to be in our fifteenth year of offering our digital know-how to companies across the globe, and we value the chance to collaborate.
View Dom & Tom Profile
$150-$199/hr
$50,000+
10 - 49
New York, USA
0.0 (0 Reviews)
18
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
18
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Maximizing Engagement Through Custom Web Development Solutions
Whether you're a startup, enterprise, or global organization, our approach focuses on understanding user interactions to boost engagement and satisfaction. With over 15 years of experience delivering custom web development solutions, we have completed more than 2,000 projects across industries such as healthcare, education, eCommerce, finance, media, entertainment, travel, and automotive. Our flexible solutions cater to businesses of all sizes, including 12-month interest-free payment options. From strategy and UX design to full-stack development and digital marketing, we provide end-to-end support. Schedule a free website or marketing consultation today and let us help your business grow online.
View Summit Designs Group Profile
$100-$149/hr
$1,000+
10 - 49
Arlington Heights, USA
0.0 (0 Reviews)
11
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
11
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
Building Digital Solutions That Build Your Business
MavenPeak Solutions is a forward-thinking digital innovation partner that transforms ideas into scalable, high-performing digital products.We meet you where you are understanding your business goals and delivering technology that drives measurable growth. Our services flex to your needs: • Web Development — Building responsive, secure, and scalable web applications • Mobile App Development — Creating intuitive iOS, Android, and cross-platform apps • Custom Software Development — Developing tailored solutions aligned with your business objectives • IT Solutions & Consulting — Streamlining processes and enabling digital transformation Website: www.mavenpeaksolutions.com Address: 116 Cedar Ln, Bourbonnais, Illinois 60914, US Email: info@mavenpeaksolutions.com Phone:+1 217-960-0328
View Mavenpeaksolutions Profile
N/A
$500 - $1,500
10 - 49
Bourbonnais, USA
0.0 (0 Reviews)
0.0 (0 Reviews)
2
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
2
SF Score
SF Score is calculated using our SARM methodology to evaluate agency expertise, market presence, and overall credibility. View Ranking Methodology
We help you swiftly deliver your next app
Bitovi is a digital product consulting firm specializing in JavaScript development, UX design, and full-stack application delivery. Known for their collaborative, validation-driven approach, the team pairs clients with specialists whose expertise directly matches project needs. Bitovi has delivered major digital products for brands including Yum! Brands—building a global ecommerce platform across 50,000 locations in 145 countries—and KFC, whose app won a Webby People's Voice Award. The agency blends open-source contributions with hands-on consulting and training.
View Bitovi Profile
$150-$199/hr
$5,000+
50 - 249
Libertyville, USA
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