The 'computer system' used by Sid and Hattie was originally built by Century 21 for use in the TV series UFO (1970).
The room for the matchmaking agency was the same room used for Helping Hands jobseeking agency in Carry on Regardless (1961).
Richard O'Callaghan was not present for the food fight at the end of the film. His close-up was edited in later.
Peter Butterworth appears for only one minute during this film, the shoot only took one day to complete.