Bios
Mark Simonsen, CPA
Founding Principal
Mark Simonsen is the Founding Principal of AE Tax Advisors, bringing more than 20 years of hands-on experience in individual and business taxation to high-net-worth clients nationwide. His expertise spans complex W-2 executive compensation, equity and deferred compensation planning, S-corporation optimization, multi-entity structuring, and owner compensation strategies.
Mark holds a Bachelor’s degree in Accounting from Montana State University Billings and is a licensed Certified Public Accountant. Prior to founding AE Tax Advisors, he established Tax MT PLLC in Billings, Montana, where he built a reputation for precision, transparency, and proactive client service.
A firm believer in the client advisor model, Mark emphasizes long-term relationships built on year-round planning rather than seasonal transactions. He is known for translating intricate IRS regulations into clear, actionable strategies that help clients remain fully compliant while capturing every legal deduction and planning opportunity available. His approach combines deep technical knowledge with a commitment to education, ensuring clients understand not just the “what” but the “why” behind every recommendation.
Mark’s practice focuses on executives, physicians, attorneys, entrepreneurs, and business owners earning $500,000 or more annually who seek sophisticated, compliant tax strategies that protect and grow their wealth.
Christina Nortman, CPA
Managing Partner
Christina Nortman serves as Managing Partner at AE Tax Advisors, where she leads the firm’s tax compliance operations and advises high-earning professionals and business owners on advanced tax planning strategies. With a career built on precision, integrity, and client-centered service, Christina brings a wealth of experience in individual and business taxation to every engagement.
As a licensed Certified Public Accountant, Christina specializes in working with executives, entrepreneurs, and multi-entity business owners who face complex tax situations requiring careful coordination and forward-thinking strategy. Her areas of focus include business owner tax optimization, entity structuring, retirement and exit planning, and ensuring seamless compliance across federal and state jurisdictions.
Christina is committed to delivering white-glove service that goes beyond annual filing. She works closely with clients throughout the year to anticipate tax implications, respond to life and business changes, and implement strategies that minimize liability while remaining fully compliant with current tax law. Her detail-oriented approach and dedication to clear communication have made her a trusted advisor to clients seeking a true partner in their financial success.
At AE Tax Advisors, Christina plays an integral role in shaping the firm’s commitment to personalized attention, proactive planning, and sophisticated tax strategy for those who have outgrown traditional compliance-based accounting.