BACKGROUND: Over 90% of U.S. physicians are currently board certified. Although the American Board of Medical Specialties (ABMS) has established standards for physicians to acquire and maintain board certification, a comprehensive description of this process and its associated costs has not been performed. METHODS: Population-level data of currently active diplomates was extracted from published ABMS reports. Examination characteristics of the initial and continuing certification process were extracted from each member board website. Revenue, expenditures, liabilities, and assets of each board for the latest tax year were extracted from published IRS Form 990s. RESULTS: Between 2016 to 2023, the number of physicians with active and continuous certification increased by 14% and 33%, respectively. Initial certification had a mean of 300 questions over 6 hours, an 89% pass rate, and a cost of ,942. Continuous certification had a mean of 49 questions with 4 minutes per question, a 93% pass rate, and a cost of 63 annually. Total industry costs were estimated as ,908,864,254 for initial certification and ,101,324,085 for continuing certification. For the tax year 2022, this certification process generated 7 million in surplus and yielded 39 million net balance for all ABMS member boards. CONCLUSIONS AND RELEVANCE: ABMS board certification costs nearly billion for initial certification and an additional billion for continuing certification for currently practicing physicians over their careers. Ongoing research should evaluate the utility of the board certification system and explore ways to add value to this process.