The 'computer system' used by Sid and Sophie 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).
Peter Butterworth appears for only one minute during this film, the scene only took one day to complete.
The film's original title was Carry on Courting.