Thomas was born in Wolverhampton on 1 November 1885, the son of Elizabeth Pratt. She married George Hancox in Wolverhampton in 1897, so by 1901 Thomas was living with his step-father, mother, and siblings John H., James F., Letitia H., Sidney and William (all Pratt) at 22 Faulkland Street, Wolverhampton. The fifteen-year-old Thomas was a gardener (not domestic).
On 7 April 1904, Thomas joined the Royal Navy (service number SS500, later 231700). In 1911, he was with the Navy in Portsmouth. He served on various boats leading up to, and during, the First World War, until he was demobilised on 9 June 1919. He married Alice Cooper in Wolverhampton later that year, and they had a son, Thomas, in 1920. Unfortunately, Thomas senior died in 1922, and he is listed on the official Wolverhampton Roll of Honour, so this may still have been as a result of his service.