Thomas Oswald Belshaw was born in 1853 in Brook Green, London. He was an Electrical Engineer, and elected a member of the Royal Institution.
He was initiated aged 37 in November 1889. He became Worshipful Master in 1896 and again in 1920.
He married Ethel Causton Lockwood in 1904. Both their sons joined the Lodge; Edward Arthur Belshaw in 1912 and Capt Thomas Sydney Belshaw in 1917. they also had a daughter Dorothy Kate Belshaw.
Thomas succeeded his father in the Chair in 1921.
Thomas died on 6 Aug 1934 in Ravenscourt Park, aged 81.