Rutland County Councillor Sam Asplin (Lib Dem) has stood down as a ward member for Whissendine with immediate effect.
Coun Asplin has represented residents in the Whissendine area since October 2014 but no longer feels able to fulfil his role due to ongoing health issues.
This was announced on Friday.
Chief Executive of Rutland County Council Helen Briggs said: “We would like to thank Councillor Asplin for his hard work and service in spite of continuing ill health and wish him the speediest possible recovery.
“Going forward, a by-election will take place in Whissendine if a request for an election is received from two registered voters. An election will then be held to fill the vacant seat within 35 days, with further details made available to residents in due course.”