Mark opened Mark Sullivan Consulting, PLLC in October 2022 after a decade of tax consulting in FinTech. He is fairly new to the Phoenix area having moved here from St. Louis, Missouri in July 2020.

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Mark has over 30 years of experience, including several years with the IRS as a Revenue Officer and over 16 years as director at a firm that specialized in civil and criminal tax accounting, IRS representation and forensic accounting. He has been admitted as an expert witness for civil and criminal tax cases in both State and Federal courts. Since relocating to Arizona and returning to practice, he has concentrated on tax compliance and planning for individuals and businesses, advisory and representation services.

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Mark graduated from the St. Louis University with a Bachelor of Arts in Sociology – International Relations degree and studied accounting at Fairfield University and SUNY. He has an unlimited licensed to practice as an Enrolled Agent nationwide and is a member of the National Association of Enrolled Agents.

 

A long-time Jeep enthusiast, Mark enjoys off-roading in his 2006 Jeep Wrangler LJ around the Southwest or wherever he goes on vacation.