Georgina Chignell complained to police after discovering the calls when her itemised phone bill arrived two weeks later, Southwark Crown Court, south London, was told.
Constable Paul Hoffman, attached to Shepherd's Bush station, west London, was arrested following an inquiry.
PC Hoffman was sent to investigate two burglaries at flats in a converted Victorian house in Devonport Road, Shepherd's Bush, in July last year, said Alexander Cranbrook, prosecuting.
A neighbour living opposite who was preparing his supper later reported seeing a policeman in Miss Chignell's flat for a long time and wondered why he was making so many calls.
The 0898 numbers PC Hoffman is alleged to have contacted were widely advertised in the London area.
PC Hoffman, 36, of West Molesey, Surrey, denies three specimen charges of fraudulently using telecommunication systems with intent to avoid payment. The trial continues.