Sam grew up in Auckland and is an old boy of Auckland Grammar School. After starting out in the family market garden business in Epsom, he trained as an accountant. His substantial corporate career saw several senior financial management and accounting leadership positions at Allied Industries (part of Fisher & Paykel), DRG Stationary, and Newmans before founding his own practice in 1989. Sam also holds a Master of Tax from Auckland University, and has previously held board positions at Unitec Council for 15 years, and was the chairman of the Chartered Institute of Accountants in 1991/1992.

Today, Sam continues to be heavily involved in the Chinese community and leads a team of dedicated accountants at S.M. Chan and Partners. He is dedicated in helping his long-term and new clients create wealth through tax planning and tax efficiency, and specialises in family and trading trusts.