Production code number

A production code number, also known as the production code (PC) or episode code is an alphanumeric designation used to uniquely identify episodes within a television series. It is also broadly used for other identification purposes where a unique production number is desirable; for example, automobile manufacturers use production numbers as part of the vehicle identification number. But since each studio can freely generate its own PC format, it cannot be used universally to identify the show and episode.

While, in general, television episodes are filmed in the order they are intended to be aired in, there are circumstances in which this is not the case. In these instances, the production codes can be useful in determining the writers' original intentions.

Some "stand-alone" shows, such as The Simpsons, Law & Order or SpongeBob SquarePants, may air episodes in radically different order to how they are produced, because character development and continuity are not major aspects of production. The airing order may in the end be decided by the network, based on ratings, sweeps months, or other networks' competition.

Other, more serialized series, like Desperate Housewives, will air all of their episodes in order.

In some rare cases, shows will film episodes out of order to accommodate guest stars' schedules, or to work around main stars' movie schedules. A good example of this is The X-Files, which filmed episodes out of order in its fifth and sixth seasons to accommodate the shooting schedules of main stars Gillian Anderson and David Duchovny.

Code Formats

• General format for network and cable shows produced by NBC Universal, ABC studios and CBS studios is SYEE, where S is the variable letter show identifier, Y is the season number and E is a two digit episode number during that season. The code is only used on internal marketing material and feed slates.
• 20th Century Fox format for free-to-air network produced shows is YSSSEE, where Y is the season identifier from 1 to Z, S is the three letter show identifier and E is a two digit episode number during that season. Off-network produced shows after May 2011 is SSSYEE, previous codes were only numerical values in the form of S-Y-E. These are burned-in on the end copyright slate.
• Warner Brothers format for picked-up weekly produced shows is SSSSEE, where S is the combined four character alphanumeric show and season identifier and E is a two digit episode number. Daily produced shows use YYYEEE, where Y is a three digit yearly count and E is a three digit episode count during that year. Pilots use a 6 digit episode number. These are burned-in on the end copyright slate.
• Paramount Pictures format for weekly produced shows is SSSSS-EEE, where S is a five digit show number and E is a three digit episode number. Daily produced shows is SE, where S is the variable letter show identifier and E is a variable sequential digit episode count. Only the episode portion is used on internal marketing material and feed slates.
• A number of Canadian and Australian produced shows use the ISAN format, which is burned-in on the end copyright slate.