Thomas Fairfax, 6th Lord Fairfax of Cameron (22 October 1693 – 9 December 1781) was a Virginia landowner during the 18th century.


In 1748, Lawrence Washington, the son-in-law of Fairfax' cousin, introduced his brother George to Fairfax. George was impressed with Fairfax, who was one of the most powerful landowners in Virginia. Fairfax took a liking to George, noting his riding skills and love of mathematics.

As such, he offered George to work for him as a surveyor, tasking him with travelling to the valleys of the Allegheny Mountains in northern Virginia. With Fairfax owning a vast amount of unexploited land there, George was to map the region and define lots for new plantations.

By 1752, George was named adjutant general by the Virginian government, which had noted his reputation as a skilled surveyor. George admitted in his diary that he partly owed this success to Fairfax.