Isthmian League 2016–17

The 2016–17 season will be the 102nd season of the Isthmian League, which is an English football competition featuring semi-professional and amateur clubs from London, East and South East England. Also, it is the eleventh season for the current incarnations of the Division One North and Division One South.

The league constitution was announced on 12 May 2016.

Premier Division
Farnborough were required by the Isthmian League to pay their creditors in full before the league's 2016 AGM. If this was not fulfilled, the league would relegate the club from the Premier Division to Step 4, and Burgess Hill Town would be reprieved from relegation.

On 12 May 2016 league constitution was announced. The Premier Division will feature six new clubs:
 * AFC Sudbury, promoted as champions of Division One North
 * Folkestone Invicta, promoted as champions of Division One South
 * Harlow Town, play-off winners in Division One North
 * Hayes & Yeading United, relegated from National League South
 * Lowestoft Town, relegated from National League North
 * Worthing, play-off winners in Division One South

Division One North
On 12 May 2016 league constitution was announced. Wroxham were reprieved from relegation as a level 8 club with the best record among clubs, finished in the relegation zone, due to lack of promoting level 9 teams. One Division One North club were moved to the parallel division: Cray Wanderers were transferred to Division One South.

Thus, Division One North will feature five new clubs:
 * Bowers & Pitsea, promoted from the Essex Senior League
 * Brentwood Town, relegated from the Premier Division
 * Norwich United, promoted from the Eastern Counties League
 * VCD Athletic, relegated from the Premier Division
 * Ware, transferred from Southern League Division One Central

Division One South
On 12 May 2016 league constitution was announced.

Division One South will feature five new clubs:
 * Cray Wanderers, transferred from Division One North
 * Godalming Town, transferred from Southern Football League Division One Central
 * Greenwich Borough, promoted from Southern Counties East League
 * Horsham, promoted from the Southern Combination League
 * Lewes, relegated from the Premier Division