It is in the 4th tier of the Thai football league system.

Promoted from the 2017 Thailand Amateur League Central Region Promoted to the 2018 Thai League 3 Lower Region Promoted to the 2018 Thai League 3 Upper Region Relegated from the 2017 Thai League 2 Relegated to the 2017 Thailand Amateur League Central Region

Ratchaburi Mitr Phol B and Suphanburi B were taking a 1-year break.

If all of head-to-head still tie, must to find the home team from penalty kickoff on the end of each second leg match (This penalty kickoff don't bring to calculate points on league table, it's only the process to find the home team on third leg).

Updated to games played on 25 August 2018Source: Thai League 4 Source: Thai League 4 Note:Unk.1 Some error of T4 official match report 28 April 2018 (IPE Samut Sakhon United 1–1 Nonthaburi).