2019 Thai League 3 Lower Region is the 3rd season of the Thai football league. It is a part of the Thai League 3 and the feeder league for the Thai League 2. A total of 14 teams will compete in the league this season.
Two clubs were promoted from the 2018 Thai League 4
A clubs were promoted to the 2019 Thai League 2
A club was relegated to the 2019 Thai League 4 Bangkok Metropolitan Region
A club was relegated from the 2018 Thai League 2
<onlyinclude></onlyinclude>
<small>Source: Thai League 3 </small><br /> <small>Note:</small><br /><small> Some error of T3 official match report 14 July 2019 (Ranong United 1âÂÂ1 BTU United).</small>