Joan Bates (née Collins; 2 September 1929 – 10 March 2016), also self-styled as Princess Joan of Sealand, was the wife of Paddy Roy Bates, a British entrepreneur who founded the self-proclaimed micronation known as the Principality of Sealand.

[4] Joan met British Army major Paddy Roy Bates at the Kursaal dance hall in Southend-on-Sea.

[8] Bates died on 10 March 2016 at a Leigh-on-Sea, Essex, nursing home, following a long illness.

[4] Her funeral was held on 17 March, with her coffin draped with the flag of Sealand.

[3] Bates featured on at least one postage stamp issued by the Principality, as well as coins inscribed "Princess Joan".