Aby is a village in the East Lindsey district of Lincolnshire, England. It is situated approximately east from the city and county town of Lincoln, and south-east from Louth. Aby is part of the civil parish of Aby with Greenfield,
The village's name is of Old Norse origin, and means "village on a river" (Old Norse á, river, and býr, village). The villages of Åby in Sweden and Aaby in Denmark have names of identical origin and meaning.
Aby’s 13th-century All Saints Church fell into disrepair and was demolished by Sir Henry Vane in 1660. The stone was removed to Belleau for use on the Manor House. In 1888 a pitch pine Chapel was erected on the original site, but all that remains today is the churchyard.
Aby railway station opened in neighbouring Claythorpe in 1848, and closed in 1961. Before the railway line was closed, the village had the distinction of the shortest station name on the British network.
Aby's public house is The Railway Tavern.