Certified Public Accountants are U.S. accountants who fulfilled the "three Es": education, examination, experience. Generally, to sit for the Uniform CPA Examination, a candidate must have 120 hours of post-secondary education, but this varies by state/territory. The CPA license is granted by individual state boards, which together form the National Association of State Boards of Accountancy (NASBA). Experience is not necessarily required before taking the exam (check your jurisdiction), but to retain a CPA license, experience is required.
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