Named after a river that runs through the region of the founder clubs, the Rother League is the main competition for the year. Swimmers from 10 years to Open age compete in 3 rounds swum in June, July and September (and a separate Junior Trophy competition). Each round has a different programme, including a relay gala.

In 2011 the Junior Trophy gala was merged with the Premier League Gala. Results for the merged gala can be found under Premier League results.

Information, programme and overall results can be found at Hants & South Coast Leagues.