Whitton Island is an island situated at the western end of the Humber Estuary in northern England. The almond-shaped island straddles the county boundary between the counties of East Riding of Yorkshire to the north and North Lincolnshire which otherwise runs over tidal water roughly along the centre line of the estuary. Parts of the island fall within the boundaries of four civil parishes. Despite its name the largest part of the island is in the Yorkshire parish of Blacktoft and much of the remainder is in the neighbouring parish of Broomfleet. Much smaller parts of the southeast coast of the island fall within the Lincolnshire parishes of Alkborough and Whitton.