Top 100 Software Development Companies in Seattle

Founded in 2010 in Seattle, Billberry is a software development studio creating custom software, web apps, and digital products in partnership with some of the world's biggest brands. They have a veteran team of fewer than 50 strategists, designers, and developers who work in partnership with clients to help them grow, innovate, and move their businesses forward. Clients include businesses of all sizes in various industries, including business services, consumer products and services, and financial services.

Founded in 2007, Theorem is a software development firm. The midsize team specializes in custom software development, ux/ui design, IoT development, IT strategy consulting, and more. The company is based in Los Angeles, California; Santa Monica, California; New York, New York and San Francisco, California.

Beyondsoft Consulting is a business IT and consulting company based in Bellevue, Wash., with offices in Torrance, Calif.; Singapore; Beijing; Noida, India; and Kyiv, Ukraine. The company, founded in 1995, has more than 10,000 employees and provides BI & big data consulting & SI, cloud consulting & SI, IT strategy consulting, custom software development, and enterprise app modernization services. Beyondsoft Consulting serves enterprise and mid-market companies in various industries that include IT, automotive, and financial services.

A full-service digital design and development agency, Flower Press Creative Studio takes on mobile app, web, and custom software development projects. Founded in 2001, the small team of 6 is headquartered in Seattle and also has experience in UI/UX design.

Culture Foundry is a web agency founded in Seattle in 2010 with more than 10 employees. They specialize in digital strategy, web design, and web development solutions for small and mid-market firms in the fields of arts, IT, and financial services.

Zazz is a Seattle-based mobile app development company founded in 2011. They have an additional office in San Francisco. Their team of approximately 50 employees serves clients of all sizes and industries. In addition to app development, they also specialize in enterprise app modernization and UX/UI design.

Lunarbyte.io is a development agency based in Seattle. Since 2019, the 3-person team has built websites, custom software, and mobile apps for predominantly small businesses.  

ThirstySprout is an outsourced development company headquartered in Seattle with an additional office in San Franciso. Founded in 2017, they currently have about 18 employees. They provide IT staff augmentation as well as custom software and web development services to primarily midmarket agencies in IT, e-commerce, and business services.

Pwrteams is an IT company that was founded in 2007. Headquartered in Luxembourg, they have service centers in Poland, Ukraine, Bulgaria, Estonia, Lithuania, Serbia and Mexico. They are made up of 700+ employees and specialize in IT and engineering staff augmentation and building dedicated teams in Eastern Europe and Latin America. They also provide on-demand software testing, and Team as a Service for businesses of all sizes.

Affirma Consulting is a full-service technology consulting agency. Founded in 2001, Affirma Consulting is based in Seattle, WA with additional offices in Los Angeles, CA, India, Ireland, and Reno, NV. The team of 200+ focuses on consulting for Business Intelligence (BI), Sharepoint, Salesforce, and customer relationship management (CRM) software, they also offer design, marketing, and mobile and web development.

Jelvix is a software development agency founded in 2011. Headquartered in Beersheba, Israel, they also have an office in Kharkiv, Ukraine. With a team of 62 employees, their services include IT staff augmentation, mobile app development, and web development. They primarily serve midmarket clients in the healthcare and medical, financial services, and IT industries. 

Vinova is an app and game development service based in Singapore. Founded in 2010, the team of 35 employees specializes in mobile app development, web development, and custom software development. They work with small businesses, midmarket businesses, and enterprises, focusing on information technology and gaming.  

AccelOne is a software development company based in Kirkland, Wash. with offices in Buenos Aires, Argentina. Founded in 2013, AccelOne's team of 25 employees provides custom software development, mobile app development, and UX/UI design services.

Founded in 2000, UpTop specializes in UI/UX design but also shines in web and mobile app development. Their team of 50+ are passionate about solving complex problems and increasing revenue for their clients.

Mobcoder is a software development company based in Seattle. They also have an office in Noida, India. Founded in 2014, their team of 40 employees provides mobile app development, custom software, and web development services to its midmarket and small business clients. They also serve enterprise clients. 

Black Antelope is a digital creative industry headquartered in Seattle. It was founded in 2009 and has expanded to additional locations in Sacremento, Calif. and London. Black Antelope has about 3 employees that serve a range of enterprise and small- to mid-sized businesses. Services include custom software development, web development, and web design. 

Slashdev is a small software development company. The Winter Park, Florida-based company was established in 2021. Their services include custom software development, web development, mobile app development, wearable app development, and more.

TECLA is a staff augmentation firm with offices in Seattle, Mexico, Lima, Peru, and various other South American countries. Since 2012, their small team of around 10 specializes in custom software, web, and e-commerce development.  

Smashing Ideas is a mobile app development company that offers an array of services such as UI/UX design, web design, data strategy and analytics, and quality assurance and testing. Since its founding in 1996, Smashing Ideas has grown to over 50 employees who are passionate, curious, and creative.

Northwest Independent Ruby Development is a digital agency based in Seattle. Since 2011, the small team of four has specialized in providing web and custom software development. 

Large mobile app development company Room 8 Group, is located in Limassol, Cyprus. Launched in 2011, the team focuses on mobile app development, web development, application testing, ux/ui design, and more.

Founded in 2014, PYCOGroup is a development firm. Their team of around 370 employees is based in Brussels, with an additional office around the globe. They focus on custom software, web, and mobile app development.

New Normal, founded in 2012, is a software services agency headquartered in Seattle. Their company consists of a team of 22 people who specialize in web development, mobile app development, and e-commerce development. While they mostly work with mid-market businesses, they also work with enterprise and small businesses. The businesses they work with are mostly in the advertising & marketing, e-commerce, and financial services industries.
 

Scalex Technology Solutions is a digital agency founded in Bellevue, Wash. in 2015 with fewer than 50 employees. They specialize in cloud consulting, mobile app development, and custom software development for clients in the fields of education, financial, and IT services.

Virtuosity Consulting, a custom software development firm, was launched in 2008. They are located in Bellevue, Washington and Navi Mumbai, India and have a midsize team. Their services include custom software development, IT managed services, enterprise app modernization, web development, and more.

Insight Global, a HR agency, was established in 2001. Headquartered in Atlanta, Georgia; Birmingham, Alabama; Huntsville, Alabama and Phoenix, Arizona, their large team provides HR services.

E-commerce development firm Neighborsoft.team was established in 2009. Their midsize team is headquartered in Bellevue, Washington. Neighborsoft.team provides e-commerce development, web development, custom software development, mobile app development, and more.

Gaper is a software company founded in San Francisco in 2018. With over 250 professionals, they provide IT staff augmentation, custom software development, and AI solutions to clients ranging from small companies to large businesses.