The Welsh Rugby Union (WRU) has told clubs they can play matches with 12 players in a bid to fulfil fixtures for the rest of the season.
A raft of lower-league matches have been called off during the 2022-23 campaign because of teams not being able to raise sides and bad weather.
Now the WRU has written to the clubs informing them they can play with 12 players as long as both sides agree.
The governing body say they want "all clubs to continue beyond this season".
Reduced numbers games are common at mini and junior levels in Wales and the WRU's move replicates initiatives attempted in some other rugby countries, including England.
The WRU had claimed this year they have the most players registered since digital records began, but that has not stopped a significant number of games being called off.
The WRU Competitions Committee (CMC) and Community Game Board (CGB) met to "discuss the matter of the number of outstanding fixtures that are due to be rearranged and played before the end of the season".
They decided on two steps to ensure all clubs are given the opportunity to complete their fixture programmes.
The first was the reduced numbers for fixtures which outlined that teams can begin a league game with teams as few as 12 players per side as long as both teams agree.
Teams were "strongly encouraged to adopt this approach as it ensures the fixture begins in a fair and equitable manner".
Numbers to be agreed beforehand could be 12, 13 or 14 with uncontested scrums.
If one team had 20 players in their squad, all eight replacements could be used.
Reduced-numbers games will not need to be abandoned should a team lose a player, unless there is a difference of four players between the clubs.
The second step covered the awarding and claiming of league points from "the high number of unfulfilled fixtures due to teams being unable to raise a side on scheduled weekends".
The committee decided that from Saturday, 7 January that teams can be awarded or have to forfeit points retrospectively.
The WRU says this decision has been taken to ensure all leagues are completed at the conclusion of the 2022-23 season to ensure the 2023-24 season structure can be implemented and that all clubs are in a position to continue beyond this season.