Harmby is a village and civil parish very near Leyburn, in the Richmondshire district of North Yorkshire, England. It is closely connected with Spennithorne, half a mile away. The sports associations of the two villages are linked.
The waterfall at Harmby is accessed by footpath from the main road, near the top of Harmby Bank.
Prior to the nationwide municipal reorganization of 1974, Harmby was located in Leyburn Rural District. Historically, it was located in the ecclesiastical parish of Spennithorne in the Hang West Wapentake.