William Leighton (Lord Mayor of London)

Sir William Leighton (1752 – 23 April 1826) was a British shipowner and merchant who served as the Lord Mayor of London in 1806.

Leighton's family was from County Durham in the North East of England and he moved to London around 1779 following his father's death. Leighton worked as a coal merchant shipping coal from the port of Newcastle, and was based at Newcastle's Coal Exchange.

Leighton was a prominent shipowner who owned Borrowdale, Fishburn and Golden Grove, three of the ships of the First Fleet, which transported convicts to the British colony of New south Wales. Leighton also owned several ships that were sent as military transports to the British Province of Quebec with contracts from the British Navy.

Because of his maritime interests, Leighton served on various shipping committees.