2018–19 Isthmian League

The 2018–19 season was the 104th season of the Isthmian League, which is an English football competition featuring semi-professional and amateur clubs from London, East and South East England. This was also the first season to consist of four divisions after the league reorganised the former South Division into the new South Central and South East divisions. The league was also known as the Bostik League under a sponsorship deal with Bostik.

Premier Division
At the end of the previous season a new step 3 division was created under the Southern Football League, while the number of clubs in the Premier divisions was reduced to 22 for this season. The Premier Division consisted of 22 clubs: 13 clubs from the previous season, and nine new clubs.
 * Promoted from the North Division:
 * Hornchurch
 * Haringey Borough
 * Potters Bar Town


 * Promoted from the South Division:
 * Carshalton Athletic
 * Corinthian-Casuals
 * Lewes


 * Transferred from the Southern League Premier Division:
 * Bishop's Stortford


 * Relegated from the National League South:
 * Bognor Regis Town
 * Whitehawk

North Division
North Division consisted of 20 clubs: 16 clubs from the previous season, and four new clubs:
 * Promoted from the Eastern Counties League:
 * Coggeshall Town
 * Felixstowe & Walton United


 * Promoted from the Essex Senior League:
 * Basildon United
 * Great Wakering Rovers

South Central Division
At the end of the previous season a seventh step 4 division was created under the Isthmian League, as the South Division clubs were distributed between new South East and South Central divisions. The number of clubs in the step 4 divisions was reduced to 20 for the next season. The following teams were allocated to the South Central Division.


 * Remained from the South Division:
 * Chipstead
 * Molesey
 * South Park


 * Transferred from the North Division:
 * Cheshunt
 * Hertford Town
 * Waltham Abbey
 * Ware


 * Promoted from the Combined Counties League:
 * Bedfont Sports
 * Westfield


 * Transferred from the Southern League Division One East:
 * Ashford Town
 * Chalfont St Peter
 * Egham Town
 * Hanwell Town
 * Hayes & Yeading United
 * Marlow
 * Northwood
 * Uxbridge


 * Plus:
 * Bracknell Town, promoted from the Hellenic League
 * FC Romania, promoted from the Essex Senior League
 * Tooting & Mitcham United, relegated from the Premier Division

South East Division
At the end of the previous season a seventh step 4 division was created under the Isthmian League, as the South Division clubs were distributed between new South East and South Central divisions. The number of clubs in the step 4 divisions was reduced to 20 for the next season. South East Division consisted of 20 clubs: 16 clubs from the previous season South Division, and four new clubs:
 * Promoted from the Southern Combination League:
 * Haywards Heath Town
 * Three Bridges


 * Promoted from the Southern Counties East League:
 * Sevenoaks Town
 * Whitstable Town

League Cup
The 2018–19 Alan Turvey Trophy (formerly the Isthmian League Cup) was the 45th season of the Alan Turvey Trophy, the cup competition of the whole Isthmian League.

Calendar
The Isthmian League Cup was voluntary this season. Five clubs decided not to take part in the competition:
 * Brightlingsea Regent
 * Cray Wanderers
 * Dereham Town
 * Guernsey
 * Lewes

Preliminary round
Twenty-six clubs participated in the Preliminary round, while fifty-one clubs received a bye to the First round.

First round
Thirteen clubs to have made it through the preliminary round were entered into the draw with fifty-one clubs who got byes, making sixty-four clubs.