Boston United Reserves will play in the league for the fourth successive campaign in 2013-2014, under the guidance of Nigel Vince, Aidie Daubney and new coach Paul Ward.
Newcomers Grantham Amateurs will become the first member club to play their home matches outside the county — in the Leicestershire village of Waltham on the Wolds.
Grantham take the place of Boston Town Reserves, who have resigned from the league.
All other clubs were re-elected into the league, which kicks off again on Saturday August 17.