Platform Accounting Group announced Pottsville-based St. Clair & Associates has joined Keystone Advisors. This is Platform’s second location in Pennsylvania and further expands its reach in the Northeast marketplace.

St. Clair & Associates and its predecessor firms have served the community for over 50 years and provide accounting, bookkeeping, tax preparation, payroll and related compliance and advisory work for small businesses and individuals.

Keystone Advisors has maintained its success and longevity in the community because of its dedication to high standards, seasoned tax professionals and quality work ethic and product. They provide expert tax preparation, business valuation and consulting services for individuals and businesses across several industries, including Construction, Dentistry, Healthcare, Law Firms, Manufacturing and Real Estate.

“We are thrilled for this next chapter as part of the Platform ecosystem,” said Bill Kirwan, principal at St. Clair & Associates. “For decades, we have worked to build strong relationships with each of our clients so we can properly understand their needs and provide the highest quality of services. Now with Platform’s expanded resources and services, we can offer even greater support to our clients and our team.”

Platform Accounting Group is on the 2026 Accounting Today Top 100 Firms list, and has nearly 1,000 employees across 15 states. Platform is continually building out an ecosystem to provide collaborative, best-in-class professional services from tax to wealth management, ERP consulting, business accounting services and more.