He was the son of a coal miner and migrated to Australia with his family at the age of seven.
He was educated to elementary level and began work as a coal miner in the Hunter Region when he was 14.
Chalmers supported Ben Chifley in the 1920s and 1930s and remained loyal to the Federal Executive of the ALP during the party divisions in those years (see Lang Labor).
In 1947, Chalmers was elected to the New South Wales Parliament as the Labor member for Hartley at the by-election caused by the resignation of the sitting member Hamilton Knight who accepted a position with the Commonwealth Industrial Commission.
This article about an Australian Labor Party member of the Parliament of New South Wales is a stub.