Killerby is a hamlet in the borough of Darlington and the ceremonial county of County Durham, England. It is situated a few miles to the west of Darlington. In 2021 the parish had a population of 62.
In the Imperial Gazetteer of England and Wales (1870–72) John Marius Wilson described Killerby:
 ;templatestyles src="Template:Blockquote/styles.css" / ;KILLERBY, a township in Heighington parish, Durham; 7 miles NW of Darlington. Acres, 605. Real property, £1, 063. Pop., 109. Houses, 20. This place is a meet for the Raby hounds.
Etymology.
The name "Killerby" is of Old Norse origin. The first element is the given-name "Kilvert" and the second is "bȳ" meaning "farm". Spellings of the place-name suggest the first element was mistaken for Old French "culvert" ("freeman").
Demographics.
At the 2011 Census the population was less than 100.
References.
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External links.
 Media related to at Wikimedia Commons