During the early years, the Calendar title had been used by various programmes produced by YTV in both news and other genres, including the short-lived Good Morning Calendar breakfast show; the parliamentary programme Calendar Lobby; and Calendar Catwalk, a fashion show.
The name Calendar was also attached to the local version of the Channel 4 launch show, Countdown, which ran for one series on Yorkshire Television before the start of Channel 4 as Calendar Countdown. Shorter bulletins are called Calendar News.
The programme celebrated its 40th birthday on 29 July 2008 with a pan-regional special.
Upon gaining the Belmont transmitter in 1974 from Anglia Television, which served south Lincolnshire and north Norfolk, the programme developed a small regional opt-out for that area in the main programme. At the same time YTV inherited the Anglia news office in Grimsby, Lincolnshire and opened a further one in Lincoln.
During the 1970s and early 1980s, Calendar's output consisted of a main evening show and lunchtime and late night bulletins on weekdays with no bulletins at weekends. Weekend bulletins were introduced during the late 1980s. When ITV Schools programming was moved to Channel 4 (Channel 4 belonged to ITV until 1993) in 1987 and daytime programming introduced to ITV, morning bulletins were introduced at 9:25am and 11am along with a mid-afternoon bulletin. By the mid-1980s, Calendar had expanded its lunchtime bulletin into a half-hour magazine show entitled Calendar Lunchtime Live. The programme was scrapped in the early 1990s but reintroduced for a short period in 2001.
The mid-morning and lunchtime Calendar News bulletins were split into three sub-regions. Calendar East (Hull) was broadcast to east Yorkshire, Lincolnshire and North Norfolk, whilst Calendar South was broadcast to Sheffield and north Derbyshire and Calendar News was broadcast to the rest of the region (west and north Yorkshire). There was also a 5- minute opt-out within the main Calendar programme.
Calendar North: (North, West & Southwest Yorkshire and North Derbyshire i.e. Chesterfield)
Calendar South: (central & east Lincolnshire, East & Southeast Yorkshire, east Nottinghamshire i.e. Newark, and north Norfolk).
Calendar airs on ITV Yorkshire seven days a week. ITV Yorkshire provides three news bulletins during GMTV. The mid-morning bulletin airs immediately after an ITV News Summary at 11.15, during This Morning, this update airs for 5 minutes. The lunchtime edition of the programme follows on from the ITV Lunchtime News, giving a five minute round-up of the days developments between 13:55 and 14:00. The main evening edition of Calendar begins at 18:00, and ends at 18:30. The late news update from Calendar follows the News at Ten, airing between 22:25 and 22:40 Monday to Thursdays, and between 23:25 and 23:40 on Fridays, after The Late News.
Calendar airs four bulletins at weekends: two on Saturday and two on Sunday. Times vary, but the Sunday evening bulletin usually airs at around 18:30.
As with many ITV regional news programmes, some areas of the YTV region crossover into neighbouring ITV regions. For example, Calendar South covers Newark, which is also covered by Central News East; whilst north Norfolk is also covered by Anglia Tonight.