A mechanical pencil or propelling pencil is a pencil containing an internal mechanism which pushes or propels the thin graphite lead through the tip. Like standard pencils, there are also mechanical pencils which have a rubber eraser on the end. Mechanical pencils provide lines of consistent thickness, well suited for technical applications such as drafting and writing.

The mechanical pencil was first invented in Britain in 1822 by Sampson Mordan and Gabriel Riddle. Earliest Mordan pencils are thus hallmarked SMGR. Sampson Mordan continued manufacturing pencils and a wide range of silver objects until the second world war when their factory was bombed.