Warren Johnstone

Warren Johnstone

Deputy Chair, BDO New Zealand; Audit & Assurance Partner; International Liaison Partner for BDO New Zealand

Accounting & Technical Services | Financial Statement Audits | Internal Audit | Risk Advisory | Special Purpose Audits & Reviews


Warren has more than 25 years of accounting and audit experience. He has been a Partner in the Assurance Services division of BDO Christchurch for the past 22 years and was previously the Managing Partner of BDO Christchurch.

Prior to his time at BDO, Warren worked for a number of New Zealand’s leading financial institutions and gained valuable international experience in the United Kingdom. 

Warren has significant experience in the education sector as the auditor for more than 230 schools in the South Island. He is also involved in a variety of special assignments including education reviews, governance assignments, fraud investigations and arbitration/mediation work.

Warren has a particular interest in professional services firms, strategic planning, profit share models and transparent systems and processes. His audit experience is vast, with clients in most sectors and industries including retail, importing, exporting, finance, forestry and wholesaling. 

In his twelve years as Managing Partner of BDO Christchurch, he has overseen a significant merger and growth that has seen the firm almost triple in size.

Warren is an appointment member of the BDO New Zealand National Board.



  • Chartered Accountant (Chartered Accountants Australia & New Zealand)
  • Fellow of Chartered Accountants (Chartered Accountants Australia & New Zealand)
  • Holder of Public Practicing Certificate from the New Zealand Institute of Chartered Accountants
  • Licenced Auditor with the Financial Markets Authority
  • Approved Auditor with the Office of the Auditor General
  • Registered Company Auditor with the Australian Securities & Investment Commission (ASIC)

Professional Affiliations

  • Fellow of Chartered Accountants Australia & New Zealand
  • Member of New Zealand Institute of Directors


  • Bachelor of Commerce 

Community Involvement 

  • Past Board Chair of St Bede's College, Christchurch, for 10 years
  • Past trustee of the North West Community Sporting Trust
  • Past Chair of the New Zealand Institute of Chartered Accountants Earthquake Recovery Committee
  • Board member of New Zealand Red Cross
  • Board member of New Zealand Red Cross Foundation