Firefighters from Metheringham were called to a report of a fire in a utility room.
The incident was called in at 10.41am at a property on Park Lane, Billinghay.
A fire service spokesman reported fire damage to the top of a fridge freezer and contents of an ashtray.
This was believed to have been caused by carelessly discarded smoking materials.
The occupant had put the fire out, without injury, before the crew arrived.