Get to Know Me

Based in the firm’s Whippany office, Zsia is a partner and Tax Leader of the firm’s Technology and Emerging Growth Services practice with over 20 years of professional experience specializing in taxation including private and publicly held multistate and multinational companies. She has a deep expertise assisting corporate clients with ASC 740 Tax Provisions and Tax Compliance.

Zsia leads the Tax Tech and Emerging Growth Industry Group where she consults on a wide variety of related tax issues including diligence ready assessments, secondary transactions, qualified small business stock, tax credits and incentives (i.e. R&D, excelsior, QETC), state taxes including sales tax and international taxes. Zsia is the Founder and leader of the Firm’s Women in Technology Group.

She resides in Somerset County, NJ. Previously, she was a partner at a large national accounting firm and a senior manager at a “Big Four” firm.

Let’s get started with a conversation today.

Contact Me

Give Back

Zsia is a presenter and speaker on various issues within the technology community. She has a passion for mentoring women Founders and Executives. She spearheads networking events, seminars, and dinners / happy hours that enable women to grow their network and community.

Awards and Accolades

Zsia is also the Co-Leader of “Women of Withum’s” empowerment program, which focuses on the elevation and inspiration of women. She is a dynamic and devoted leader, and among other recognitions, was named one of New Jersey’s 2019 Best 50 Women in Business by NJBIZ. In 2010 Zsia was honored as “Woman of the Year” by the American Woman’s Society of Certified Public Accountants of New Jersey.

Zsia is selected by Profiles in Diversity Journal as a “Woman Worth Watching in STEM” in 2022 and named by ROI-NJ as “Women in Business Influencer” in 2022.

Latest Thinking

Withum’s Zsia Rosmarin named to Profile in Diversity Journal’s "Women Worth Watching® in STEM" List

Withum is proud to share that Zsia Rosmarin, Partner and Team Leader of Technology and Emerging Growth Services, was honored as a Woman Worth Watching in STEM by Profiles in […]

Learn More
What to Know About the Canadian GST/HST

Share Proposed amendments to the draft legislation for non-resident registration requirements were released in April 2021. They include, among others: a safe harbor for platform operators limiting liability for failure […]

Learn More
Image of Rhonda Maraziti and Zsia Rosmarin.
Two Women of Withum Garner Spots on 2021 ROI-NJ Women in Business Influencers List

Withum is honored to have two women leaders, Zsia Rosmarin and Rhonda Maraziti, among the 2021 ROI Influencers: Women in Business class. ROI-NJ released its 2021 ROI Influencers: Women in […]

Learn More