2003–04 Eastern Counties Football League

The 2003–04 season was the 62nd in the history of Eastern Counties Football League a football competition in England.

AFC Sudbury were champions, winning their fourth Eastern Counties Football League title in a row after the new club was formed in 1999, while Maldon Town were promoted to the Southern Football League for the first time in their history.

Premier Division
The Premier Division featured 20 clubs which competed in the division last season, along with two new clubs, promoted from Division One:
 * Halstead Town
 * King's Lynn reserves

Division One
Division One featured 17 clubs which competed in the division last season, along with four new clubs:
 * Ely City, relegated from the Premier Division
 * Harwich & Parkeston, relegated from the Premier Division
 * Ipswich Wanderers, relegated from the Premier Division
 * Kirkley, joined from the Anglian Combination