Baron Deincourt was a title which was created twice in the Peerage of England. It is now extinct.
The first creation was by writ on 6 February 1299 in the reign of Edward I when Edmund Deincourt was summoned to the House of Lords. It went into abeyance on his death in 1327.
The second creation was on 27 January 1332 in the reign of Edward III when William Deincourt, nephew of the above, was also summoned to Parliament. The title then passed down in the family to William Deincourt, the fifth Baron and went into abeyance on his death in 1422.