Thomas was born in Wolverhampton in 1891, the brother of John Garner. By 1911, he was a visitor at the home of Martin Cunniffe, of 181 Oxford Street, Bilston. Thomas was a labourer on the railways. In 1915, he married Mary A. Reynolds in Wolverhampton, but the couple do not appear to have had any children.
In August 1914, Thomas enlisted with the 1st/6th Battalion of the South Staffordshire Regiment (number 2746 and later 240480). He first served in France on 5 March 1915. He was promoted to Serjeant, and later awarded the Military Medal (the third Tettenhall man to receive it), as noted in the London Gazette on 13 November 1918. He received it for digging out one of his men who had been buried by a heavy shell, while he was himself under heavy shell fire. Unfortunately, he was himself killed in action on 21 August 1918. His commanding officer wrote to his wife at 80 Aldersley Road, Tettenhall, stating that “He was my bravest sergeant, and did not know what fear was. He repeatedly did acts of bravery, and was a grand example to his platoon.” His death was reported in the Express & Star on 7 September 1918. The article mentioned that his brother, J. E. Garner, was also serving at the front. He is remembered at Fouquieres Churchyard Extension in France, as well as on the war memorial at St Michael and All Angels Church, Tettenhall. Further details about both brothers are available here.