The league is made up of teams from north west England and the Isle of Man; principally consisting of the English counties of Cheshire, Cumbria, Greater Manchester, Lancashire and Merseyside.

Occasionally, depending on promotion and relegation, teams from either North 1 East and North 1 West may be required to compete in the opposite league to ensure that the number of teams in the east and west leagues remains at 14 teams each.

On 30 October 2020 the RFU announced [1] that due to the coronavirus pandemic a decision had been taken to cancel Adult Competitive Leagues (National League 1 and below) for the 2020/21 season meaning North 1 West was not contested.

For the 2009–10 season the division would be renamed North 1 West as part of wholesale national restructure of the league system by the RFU leading to mass changes at all levels including in the north.

The team with the superior league record has home advantage in the tie.