Tax Services
Seattle, WA
Located in North Seattle, Withum is a leading Seattle CPA firm with a robust ERISA practice, enhanced forensic capabilities and the ability to offer outsourced accounting and cybersecurity services locally and nationwide.
Ranked in the top 25 firms in the nation, Withum’s team of passionate professionals offer advisory, tax, audit and assurance services to the Seattle business community…plus a whole suite of advisory solutions that will level up your success. That’s the Power in the Plus!
(206) 522 6370
Seattle Service Specializations
Assurance and Accounting
Forensic and Valuation Services
Cybersecurity
Outsourced Accounting Systems and Services (OASyS)
Washington State and Local Tax Updates
Do you or your organization operate in multiple states? Do you own property in a variety of states? Washington 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 Washington 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 Washington
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
Joseph M. Thiermann, CPAJoe is a partner with over 25 years of specialized audit experience with audits of defined contribution plans, defined benefit plans, health and welfare plans, labor organizations and not-for-profits. He conducts system-wide reviews, designs and implements accounting systems and works on special projects involving system design, expense reporting and compliance, often in conjunction with other professionals to resolve regulatory and general management issues for clients.
Joe is an avid public speaker, having presented at the Annual Conference of the International Foundation of Employee Benefit Plans (IFEBP), the IFEBP Accountants’ Institute and the Oregon Labor Law Conference, and even taught business courses to contractors.
Seattle Leadership
Withum in the News
Farber Hass Hurley LLP Joins Practice With Withum
LOS ANGELES, September 1, 2026 – Withum, a top 20 advisory and accounting firm, announced today that Farber Hass Hurley LLP (FHH CPAs), a public accounting and tax firm headquartered in Chatsworth, CA, has joined its practice effective September 1, 2026. “Farber Hass Hurley’s joining Withum is an important step in our continued growth on…
NJBIZ Names Two Withum Leaders to Finance Power List
Pat Walsh Pat was recognized for his relentless dedication to elevating Withum’s position as a top 20 advisory, accounting and tax firm. This recognition reflects Pat’s leadership and the Firm’s consistent year-over-year growth and strategic expansions into new markets under his guidance. His commitment and contributions to the profession have earned him numerous accolades, including…
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…
Contact Us
We will make every attempt to respond to your inquiry in a timely manner.