WSIA’s membership consists of approximately 735 member firms, all of whom operate over 1,700 offices representing tens of thousands of individual brokers, insurance company professionals, underwriters and other insurance professionals serving the U.S. wholesale, specialty and surplus lines insurance market. WSIA is unique in that both surplus lines brokers and surplus lines insurance companies are voting members of the Association; thus WSIA represents and speaks for the surplus lines wholesale marketplace.

WSIA is comprised of four membership classifications: U.S. Wholesale Member, U.S. Insurance Market Member, Associate Member, Service Member.