Orange County, CA

Located in the heart of Irvine’s business district, Withum is one of the nation’s top-rated and largest accounting firms in Orange County.

Spectrum Center office building in Orange County, California against the skyline

Withum helps local corporations and nonprofits thrive, offering advisory, tax, audit, assurance and consulting services to the Orange County business community. We are more than just an Irvine accounting firm, we are a strong national resource providing all the traditional CPA and accounting services businesses and individuals require, plus a whole suite of advisory solutions to accelerate your success. That’s the Power in the Plus!

Orange County Service Specializations

SALT-California-Updates

CA State and Local Tax Updates

Do you or your organization operate in multiple states? Do you own property in a variety of states? California 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 California 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!

California SALT Updates

Beyond the Region

  • Inside Public Accounting Top 100 Firms – 22nd 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
Inside Public Accounting Top 100 Firms 2024 logo
Certified Place to Work 2025-2026
Ken-Johnson_Web

Partner In Charge

Kenneth L. Johnson, CPA

Ken is the Partner-in-Charge (PIC) of the firm’s Orange County office. Ken brings nearly three decades of expertise in conducting audits and reviews for both privately held and publicly traded companies. 

In addition to his successful career working with and advising the firm’s clients, Ken dedicates much of his time to non-client-focused activities, such as the daily operations and people strategy of the Orange County office and its growth in the local marketplace. He is passionate about mentoring the next generation and providing them with the same opportunities he had. Ken is helping the younger team members grow the firm and contribute to this office’s legacy of entrepreneurship. By acting as a business owner first, he is setting an example to the office of the advisory experience we should bring to our clients, above and beyond the compliance work of audits and tax. 

Orange County Leadership

Eric-Gallagher_Web
Partner
Orange County, CA
Amanda-Hong_Web
Partner
Orange County, CA
Brandon-Attaway_Web
Partner
Orange County, CA
Joe-Cover_Web
Partner
Orange County, CA
Vince-Phorn_Web
Partner
Orange County, CA
Michael-Ritchie_Web
Partner
Orange County, CA
Emily-Egkan_Web
Partner, Team Leader, Construction – California
Orange County, CA

Withum in the News

Read more
BPTW-featured-image
Fortune Media and Great Place to Work Name Withum Among Best Workplaces in New York

Ranking at number 22 on the Large Business list, Great Place to Work recognized the Firm for its strong culture and team-centric approach, highlighting its distinctive benefits such as flexible schedules, childcare benefits and time off. The recognition also spotlighted Withum’s collaborative environment – prioritizing professional development, open communication, innovation and work-life balance, enabling team…

Read more
50-50-Withum-Champions-Veteran-Initiatives
Withum Champions Veteran Initiatives and Community Impact

Wreaths Across America For more than five years, Withum has been an active participant in the Wreaths Across America initiative, which is championed by the Firm’s Veterans Team Member Resource Group (TMRG) and the Not-for-Profit Services Team. Wreaths Across America (WAA), is a national nonprofit dedicated to remembering fallen service members, honoring those who serve…

Read more
042026-LATimes-Leaders-50-50
Steve Talkowsky Named NJBIZ 2026 Leader in Finance

As a respected leader, Steve was recognized for his impact on the Firm’s Tax Services Team, contributing to the practice’s growth, and for his strong commitment to the mentorship and development of the teams he leads. He serves clients with global operations, advising on business taxation matters with deep expertise in Subchapter C, S corporation and partnership taxation.  With a focus on making complex tax matters accessible, he is…

Read more
052026-ROI-NJ-Leaders-50-50
ROI-NJ Names Withum Leaders to Annual Power List

Pat Walsh Pat Walsh, Managing Partner and CEO, has led numerous firmwide strategic initiatives focused on best practices, client experience and technology. He leads Withum’s national growth strategy and client service initiatives, with a focus on innovation, talent development and expanding the Firm’s advisory capabilities to meet clients’ evolving needs. Pat was recognized for his…

Contact Us

We will make every attempt to respond to your inquiry in a timely manner.