The screenplay was adapted from the 1960 Associated Television Theatre 70 (1960) teleplay The Gold Inside (1960) by Jacques Gillies, also directed by Quentin Lawrence, and featuring André Morell (Colonel Gore-Hepburn) and Richard Vernon (Mr. Pearson) in the same roles.
Although certificated by the BBFC in June 1961, this film did not get a release in the UK until December 1963, when it went out as the support film for Bye Bye Birdie (1963).
The famous film company Hammer invested a mere £37,000 by 2009 standards for the making of Cash on Demand (1961). To optimize its budget the film uses a limited number of sets --- an interior street set, the trading area of a bank, the manager's office, the stairway between office and the vault, and the interior of the vault itself.
The £93,000 stolen would equate to about $261,000 at the time or $2.68M in 2023.