Coaching since 1988 at different schools and junior programmes like Head Tennis School and Spex 2000 Tennnis Scheme, Nelson Tan has proven and shared his extensive knowledge of the racket game with many young individuals. In 1990, he also started coaching at country clubs such as SICC and SAFRA. He was certified by SSC (1984) and USPTR (1988). He was one of the few who have achieved SLTA Level 2 in 1998 conducted by ITF. He has also conducted MOE Tennis Teachers' Course and assisted in SLTA Level 1. Nelson had received the SSC Development Coaching Award in 2004 and won several titles such as SAFRA Open singles (1983 - 1988) and Pesta Sukan (35+) singles champion (1997).

Currently, he is one of the coaches of the Pee-Wee Tennis Programme and conducts private coaching lessons.