Tully, who was born at RegentPark in Tollygunj area (then in undivided 24 Parganas district) on October 24, 1935, needs the certificate to apply for the Overseas Citizen of India status.
The birth was registered by the Registrar of Births, Deaths and Marriages, Alipore, on November 21, 1935.
He was born of William Scarth Carlisle Tully and Patience Treby.
The document, found in the Corporation archives on November 14, will be handed over to Tully at a programme in Kolkata on Tuesday, KMC Mayor-in-Council (Health) Atin Ghosh said on Tuesday.
Tully's application for his birth certificate on August 5 spurred the KMC health department into action and it was located in the archives at its headquarters.
"After receiving the request, we made a comprehensive search of our records and obtained the pre-Independence document from our archives. We are ready to hand it over to him," Ghosh, whose department is in charge of issuing birth certificates, said.
Tully was BBC's New Delhi bureau chief for 22 years since 1965 and covered major events, including the Indo-Pakistan conflicts, Bhopal gas tragedy, Operation Blue Star, assassinations of Indira Gandhi and her son Rajiv Gandhi and demolition of the Babri Masjid.
His reportage won him honours like the Padma Shri, Padma Bhushan, Order of the British Empire and Knighthood.
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