Born at North Carlton in Melbourne to carpenter William Wallis and Mary Ann, née Gorman, he attended state schools at Horsham and Moreland before becoming a cutter's apprentice and journeyman.
On his release he joined the Victorian Clothing Operatives' Union and represented it in the Trades Hall Council, also being elected to the VSP's executive.
He returned to his career in 1908 and 1909 was elected president of the Victorian branch of the Federated Clothing Trades Union of Australia.
In 1932 he was elected President of the Victorian Trades Hall Council, and in 1933 he was appointed the workers' delegate to the International Labour Conference in Geneva.
A workers' representative on the Women's Employment Board during World War II, Wallis was appointed a Commonwealth conciliation commissioner in 1947 and resigned from his union positions.