Police found cannabis on a suspect when he was taken into custody at Grantham Police Station.
Dean Michael Michniew, 25, of Chestnut Grove, Grantham, admitted possessing cannabis on August 7.
Prosecuting, Jim Clare said Michniew was taken into custody that evening on another matter and cannabis and a cannabis grinder were found in a bag. He admitted the drug was for his own use.
Stuart Wild, defending, said his client had made a full and frank confession about the cannabis. No further action was taken on the other matter. He said it was a small amount of cannabis which was consistent with personal use. His client had said it was about £25 worth, or three grams, not five grams as in the charge.
Mr Wild said Michniew had been using cannabis for a considerable time and had now referred himself to Addaction to try and kick the habit. He said Michniew worked full-time in a factory and had another part-time job. He said his client did not get involved in criminal activity to pay for the drugs.
Magistrates fined Michniew £235 and ordered him to pay £180 criminal court charge, £23 victim surcharge and £85 court costs. They also ordered the forfeiture and destruction of the drug and the grinder.