Orange County combines a dynamic business ecosystem with complex state and local tax laws—making professional financial support essential as companies scale. These top-tier CPA firms, accounting specialists, and audit advisors help OC founders stay compliant, investor-ready, and financially organized.
Withum – Orange County
A top-rated national accounting firm located in the heart of Irvine’s business district. Withum provides a “power in the plus” approach, offering specialized tax, accounting, and advisory solutions designed to accelerate the success of local corporations and tech-driven startups.
Great for:High-growth tech companies, mid-market corporations, and businesses needing a national resource for multi-state tax and transaction advisory.
Wright Ford Young & Co. (WFY)
One of the largest local CPA firms in Orange County, based in Irvine. For over 50 years, WFY has been a trusted advisor to closely-held companies, family-owned businesses, and private foundations, specializing in tax, estate, and proactive business consulting.
Great for: Family offices, private companies, and founders who prioritize high-touch communication and “no surprises” tax execution.
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Donna L. Stern, CPA
A respected local CPA offering personalized bookkeeping and tax solutions for small businesses across Orange County. With a focus on reliability and clear communication, she provides the hands-on financial management necessary for local service providers and creative agencies.
Great for:Solopreneurs, freelancers, and small teams needing consistent, high-quality bookkeeping and year-round tax support.
SingerLewak – Orange County
A premier West Coast accounting firm since 1959. SingerLewak is highly regarded for its core assurance services, helping mid-market enterprises prepare for IPOs, navigate mergers and acquisitions, and ensure compliance with complex financial reporting standards.
Great for:Growth-stage companies preparing for a major liquidity event, government contractors, and businesses requiring sophisticated audit readiness.
Aldrich CPAs + Advisors
With a strong office in Orange County, Aldrich provides robust audit and assurance services tailored to specific industries like agriculture, manufacturing, and construction. They blend technical expertise with a values-driven approach to help businesses manage risk and transparency.
Great for:Established middle-market firms and non-profits that need deep industry-specific audit expertise and financial leadership.
JLK Rosenberger
A regional powerhouse known for its strength in the insurance and real estate sectors. They provide certified financials and specialized audit services that meet the high-stakes requirements of lenders and regulators in the Southern California market.
Great for:Real estate developers, insurance agencies, and organizations facing unique industry-specific audit requirements.
Looking for personalized tax planning or certified financials? Hustler’s Library can help you connect with the right advisor. Book a consultation now to schedule a free intro.
Most founders bring in a CPA when revenue becomes predictable or when they begin planning for expansion, taxes, loans, or investor conversations. In Orange County, the competitive real estate and tech markets often require CPAs earlier to handle complex entity structures. Auditors are typically required when lenders, grant programs, investors, or regulatory agencies need certified financial statements.
CPAs in OC commonly charge flat monthly packages for bookkeeping and advisory, while audits are priced by scope, business size, and reporting requirements. While rates are higher than the national average due to the premium market, they are often slightly more flexible than top-tier Los Angeles or San Francisco firms.
Not usually. However, they are required if you’re pursuing certain types of lending, seeking venture capital, entering government contracting, or operating in highly regulated industries (like healthcare or finance).
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