The Welsh Rugby Union Division Four West (also called the SWALEC Division Four West for sponsorship reasons) is a rugby union league in Wales first implemented for the 1995/96 season.
During the course of a season (which lasts from September to May) each club plays the others twice, once at their home ground and once at the Hpme ground of their opponents for a total of 22 games for each club, with a total of 132 games in each season.
The team who is declared champion at the end of the season is eligible for promotion to the WRU Division Three West.
The two lowest placed teams are relegated into the WRU Division Five West.
[1] The initial three year sponsorship was extended at the end of the 2010/11 season, making SWALEC the league sponsors until 2015.