Curtis was sold to Birmingham in March 1928 for a £3,000 fee. His transfer was completed in time for him to make his debut for the club in a 4–1 victory over Sheffield United on 12 March, and the "Athletic News" reported that he "fitted into the side perfectly, and was responsible for some really clever touches". His first full season with the club, the 1928–29 campaign, was disrupted by injury problems; he was stretchered off with a knee issue during a match against Newcastle United on 17 November 1928 that required the attention of a specialist. In the opening months of 1929, Curtis was forced to undergo a knee operation that kept him out of the side for more than a month.