The "Dear Bill" letters were a regular feature in the British satirical magazine Private Eye, purporting to be the private correspondence of Denis Thatcher, husband of the then-Prime Minister, Margaret Thatcher. It was written by Richard Ingrams and John Wells, and illustrated with sketches by George Worsley Adamson for the first five years, and subsequently by Brian Bagnall.

          The series took the form of fortnightly letters to "Bill" by his friend and golfing partner "Denis". The letters were split equally between reactionary grumblings about the state of the country and vituperative comments on contemporary politics, with regular passing references to the goings-on of a fictional collection of acquaintainces and the consumption of a quite remarkable quantity of "electric soup". "Bill", whilst never identified as such in the series, was often taken as being Denis Thatcher’s close friend Bill Deedes; indeed, Deedes later titled his autobiography Dear Bill: a memoir.

          The series ran throughout the Thatcher government, first appearing two weeks after Margaret Thatcher was elected. It spawned a number of annual editions of the collected letters, one for each year, and even a stage play, Anyone for Denis?, with creator John Wells playing the title role. A television adaptation by Thames Television was broadcast in 1982.