Tax Services
Whippany, NJ
Located in the heart of Morris County, minutes from Morristown Business District, Withum is one of New Jersey’s top-ranked accounting and advisory firms, providing reliable audit, tax and consulting services to businesses locally and nationwide.
Withum’s Whippany office has an industry focus on financial services, technology, healthcare, manufacturing, distribution & logistics and private equity. With an onsite state-of-the-art cybersecurity facility, Withum’s CPAs and professionals provide quality accounting services…plus a suite of advisory solutions to help businesses grow and thrive with the personal touch they deserve. That’s the Power in the Plus!
(973) 898 9494
Whippany Service Specializations
Accounting Advisory and Financial Reporting
Audit Services
Employee Benefit Plan Audits
Private Client Services
Wealth Management
Forensic and Valuation Services
Transaction Advisory
Cybersecurity
New Jersey State and Local Tax Updates
Do you or your organization operate in multiple states? Do you own property in a variety of states? New Jersey State and Local Tax (SALT) laws are always changing and understanding the nuances of the states that you own or operate in is challenging. In these New Jersey resources, you’ll find just a dash of the most up-to-date details on rules and regulations as state and local tax changes happen by state!
Industries We Focus on in Whippany
Beyond the Region
- Inside Public Accounting Top 100 Firms – 23rd Largest Nationally
- Accounting Today Top 100 Firms – 22nd Largest Nationally
- Great Place to Work® – Fortune Best Workplaces for Parents and Women
- Vault Top 25 Accounting Firm
Partner In Charge
Zsia Rosmarin, CPA, MSBased in the firm’s Whippany office, Zsia is a Partner and Team Leader of the firm’s Technology and Emerging Growth Services tax 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.
Whippany Leadership
Withum in the News
Los Angeles Business Journal Names Two Withum Leaders as Women of Influence in Accounting
Kimberly Ravenell, tax partner, was recognized for her commitment to client service and mentorship. With more than 30 years of experience advising high-net-worth individuals and closely held businesses, she provides tax planning and compliance guidance. Kim has played a key role in guiding her team and clients through significant industry and regulatory changes while supporting…
Sameer Uddin Named to Caseware’s 2026 30 Under 30
Advancing Audit Innovation Sameer has played a key role in advancing Withum’s use of audit technology, helping teams adopt new methodologies, improve efficiency and enhance consistency across engagements. A trusted resource for technology implementation, he has been instrumental in the Firm’s adoption of Caseware Cloud and Dynamic Assurance Solutions (DAS) applications. Driving Firmwide DAS Adoption…
Withum Team Members Named as INNOVATE100 Honorees
Leading Industry with a Tech–Forward Vision Matt Walsh, partner and practice leader of Withum’s Industrial and Consumer Products Services Team, was honored in the Finance/Accounting category for helping modernize the Firm’s technology ecosystem. His leadership has supported initiatives that enhance efficiency, streamline workflows and better align technology with evolving client needs, including work with Caseware…
Alan Iosue Named 2026 LA Times Entertainment Business Visionary
As a trusted advisor to entertainment clients, Alan helps organizations navigate the unique opportunities and complexities of an increasingly dynamic, deadline-driven industry. This recognition reflects his commitment to delivering strategic guidance that supports both immediate business needs and long-term success across Southern California’s creative economy. Alan advises production companies, professional athletes, arts organizations and closely…
Withum Ranked a Top 20 Firm Among 2026 IPA 100 Firms
The annual IPA 500 ranks the 500 largest accounting firms in the United States by net revenue using data submitted through the IPA Practice Management Survey. A Growth Strategy Guided by The Withum Way Withum’s rise into the Top 20 reflects purposeful investment. As an independent, owner-operated firm, Withum has the flexibility to make long-term investments that support sustainable growth while maintaining its culture and deepening client relationships. Innovation…
Contact Us
We will make every attempt to respond to your inquiry in a timely manner.