About William

William Haddad is an assurance director at Marcum LLP in the Costa Mesa, CA office. He has many years of experience in public accounting, serving both publicly and privately held companies. He has served clients across many sectors including those in software and technology, manufacturing and distribution, cannabis, and construction. Mr. Haddad also has extensive experience in financial reporting under GAAP, SEC reporting, and IPOs. While his focus is on predominantly middle-market companies, he works with clients throughout the United States providing financial statement audits, reviews, compilations, and agreed-upon procedures.

Mr. Haddad began his career with the Firm in 2019. Prior to joining Marcum LLP, he worked at a large regional firm and a “Big 4” accounting firm. In addition, Mr. Haddad has provided consulting and accounting services for CPA firms and various private businesses throughout the country.

Professional & Civic Affiliations

  • American Institute of Certified Public Accountants (AICPA)
  • California Society of Certified Public Accountants (CalCPA)
  • Toastmasters International, Member
Practice Focus

Financial Reporting under GAAP
PCAOB and AICPA Audits
SEC Reporting
Complex Debt & Equity Instruments and Transactions


Bachelor of Science, Accounting and Finance
Yarmouk University