2018 Thai League 4 Western Region is the 6th season of the League competition since its establishment in 2013. 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.
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In the third leg, the winner on head-to-head result of the first and the second leg will be home team. If head-to-head result are tie, must to find the home team from head-to-head goals different. 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).
<small>Source: Thai League 4</small> <small>Note:</small><br /><small> Some error of T4 official match report 28 April 2018 (IPE Samut Sakhon United 1âÂÂ1 Nonthaburi).</small>