The competition is contested in a double-round robin format, with each team playing every other team in two home-and-away matches. Points are awarded based on wins, losses, draws and ties, with the top two teams playing a final at the end of the season. Regular matches last for four days; the final lasts for five days. New South Wales have won the most titles, with 45 overall.
In 1999, the Australian Cricket Board (now Cricket Australia) announced a sponsorship deal which included renaming the Sheffield Shield to the Pura Milk Cup, then to the Pura Cup the following season.Pura is a brand name of National Foods, a wholly owned subsidiary of the Philippines-based San Miguel Corporation. The sponsorship increased total annual prize money to A$220,000, with the winners receiving A$75,000 and the runners up A$45,000.
On 16 July 2008 it was announced that Weet-Bix would take over sponsorship of the competition from the start of the 2008–09 season, and that the name would revert to the "Sheffield Shield" or the "Sheffield Shield presented by Weet-Bix". Weet-bix is a cereal biscuit manufactured by Sanitarium Health Food Company.
In the 2011-12 season, Bupa took over the sponsorship for the competition.
Each side has played each other both home and away every season with the following exceptions:
South Australia had no home game with: Victoria in 1901/02 or 1903/04; either opponent in 1907/08; New South Wales in 1910/11.
Queensland and South Australia played only once (in South Australia) in 1926/27.
Western Australia played each team only once from their debut in 1946/47 until 1955/56 inclusive.
Tasmania played each team only once from their debut in 1977/78 until 1981/82 inclusive.
Where the teams played an unequal number of games, their final points were calculated on a pro-rata basis.
Matches were timeless (i.e. played to an outright result, weather and schedule permitting) up to 1926/27. A 4-day time limit has applied since 1927/28.
Since 1982/83, the top two teams after the 10 home and away rounds have met in a final. The team with the most points hosts the final against the second ranked team. The match is played at the home ground of the top ranked team, and they only need to draw/tie that match to win the title.
Bonus Point Example - If after 100 overs the score is 8/350, the batting team would receive 1.5 points ([350-200] x 0.01), and the bowling side would receive 1 point (0.5 each for the 5th and 7th wicket)
Quotient (team's batting average divided by its bowling average) is used to separate teams which finish on an equal number of points.
Teams can be penalised points for failing to maintain an adequate over rate.
The Shield was initially envisaged as a match-by-match challenge trophy; it was originally determined on 4 January 1893 that it would first be awarded to the winner of the next intercolonial match (which was, in fact, the fourth of the season), and then would pass in perpetuity to any team which defeated the holder of the trophy; But on 30 January, it was decided instead to award the Shield to the team which won the most intercolonial matches across the season.
The quotient has been used as a tie-breaker for teams on equal points since 1893/94.
First innings points were introduced in 1932/33 and used until 1970/71.
Bonus points for first innings batting and bowling were used from 1971/72 to 1980/81 inclusive. During the first 100 (8-ball) overs of each side's first innings, a maximum of 10 batting bonus points could be attained. They were awarded for every 25 runs scored from 175 to 400 inclusive. A maximum of 5 bowling bonus points were available, initially upon capture of the second, fourth, sixth, eighth and last wickets. This was later changed to wickets 1, 3, 5, 7 and 9 as batting teams often declared when 9 wickets down to deny the bowling side the additional bonus point.
Prior to the introduction of a Final in 1982/83, the team with most points after the home and away rounds was declared the winner. With the introduction of the Final, the top team hosts the second placed team in a five-day match. The visiting team must win the Final to win the championship; the home team wins the championship in the event of a tied or drawn Final. Further details including match scorecards are available at Cricinfo and the Cricket Archive.
The Player of the Year award is announced at the end of each season. Since its inception in 1976 it has been awarded to the best-performed player/s over the season, as determined a panel of judges. Victorian and South Australian batsman Matthew Elliott has won the award the most times, being awarded Player of the Year on three separate occasions.