The official flag of Lincolnshire was unveiled at five separate ceremonies across the county on 24 October 2005.

The campaign was supported by local businesses, who saw it as a good way to promote trade and tourism in Lincolnshire.

[citation needed] The flag features a red cross, edged in yellow and bearing a yellow fleur-de-lys, on a background of green and blue quarters; in the jargon of blazon, Quarterly Vert and Azure, on a Cross Gules fimbriated Or a Fleur-de-Lys of the last.

Yellow represents the crops grown in the county, as well as the nickname "Yellowbellies" given to people born and bred in Lincolnshire.

Blue represents both the sea of the East coast and the wide skies of Lincolnshire, and green symbolises the rich lushness of fenland fields.