Paul Treinen


Paul is the Managing Principal of the Office for CLA’s Irvine and San Diego locations, formerly White Nelson Diehl Evans LLP (WNDE). He has been with the firm since 1990 and advanced to the role of Principal in 2001 and Managing Principal in 2017, where he oversaw several strategic and administrative items for the firm. Paul formerly served as the firm’s Tax Director from 1997 to 2016.

Focused and knowledgeable in corporate and pass-through taxation, Paul also has a robust individual client base. Paul also has a specific focus and specialty in senior care and aging services.  Like most Principals in our firm, Paul also has vast experience dealing with manufacturers and distributors. He also has several clients that are focused in hospitality, retail, real estate, as well. He is an ardent believer in the value of tax planning, and has extensive experience with mergers and acquisitions, transactional issues, business formations, and strategic exit strategy planning.


Bachelor of arts in business administration with a concentration in accounting from California State University, Fullerton

In the community

  • Member of Board of Governors, California State University, Fullerton Philanthropic Foundation
  • PIH Health, Director
  • PIH Health Whittier Hospital, Director
  • PIH Health Downey Hospital, Director
  • PIH Health Good Samaritan Hospital, Director
  • PIH Health Physicians, Director
  • PIH Health Insurance Company, Director