Based in Tampa, Fla., Schellman & Company, LLC is the 47th-largest CPA firm in the U.S., as measured by annual revenues. It booked $148.5 million in revenues in its latest fiscal year. Schellman has more than 900 clients, including numerous publicly traded and Fortune 500 companies.

Schellman provides attestation and compliance services. Its professional services focus on security and privacy audits, assessments, and certifications. Schellman is a globally licensed PCI Qualified Security Assessor, an ISO Certification Body, APEC Accountability Agent, and a FedRAMP 3PAO. Schellman has become one of the largest CPA firms in the United States without providing any traditional accounting services, such as financial statement audits or tax preparation services.

Founded in 2002 by Chris Schellman, the firm is led by CEO Avani Desai. It and operates out of multiple locations around the United States with a remote workforce and employs more than 500 people.