William Collier, CPA/MST



In his role as Shareholder and Tax Partner-In-Charge, Bill Collier manages the firm’s tax operations, family office group, and M&A team. He applies his highly skilled expertise to develop tax-saving ideas for our client's business challenges.  He develops internal standards governing the delivery of tax services to clients and maintains a close pulse on the legislative and regulatory changes impacting our client’s tax positions, both domestically and internationally. This tax capability, combined with many years of experience in business acquisitions and valuation, allows Bill to provide our clients a unique perspective on their M&A deals.  Those clients in need of succession planning will find tremendous value and peace of mind in Bill’s depth of knowledge in estate tax planning.  As leader of the Family Office Group, Bill brings this wide-ranging skill set to bear in a very personal manner and has become a go-to Trusted Advisor for our client base.

Throughout the course of Bill’s career, he has served as the primary tax advisor on hundreds of business acquisitions.  His client base has been global in scope, encompassing all continents except Antarctica.  As an example, Bill has been a part of tax litigation support engagements facing the Australian Tax Office and advised governments of developing territories on tax cases. Prior to joining Holsinger, Bill spent nearly a decade in the audit and tax groups of two international accounting firms, achieving the rank of Senior Manager.

Education and Certifications

  • Grove City, B.S. in Accounting
  • Masters of Taxation, Robert Morris University
  • Certified Valuation Analyst

Professional and Community Development

  • Adjunct professor in the Graduate School of Accounting at Carnegie Mellon University
  • Member of the YMCA Board of Directors and Finance Committee
  • Sunday School Teacher for senior high students at his local church, every year since 1989