What Does 10/9c Mean?

For most of my adult life, I’ve been disinterested in television. A new show came on that I wanted to see, though, so I found a way to view it. The start time said 10/9c. I was fairly certain that meant it started at 10pm everywhere. Think about “Saturday Night Live.” Networks frequently broadcast a show live on the East Coast and delay it for the West Coast viewing. The Central Time Zone appears to be somewhat of an exception. Something airing live at 10pm on the East Coast might not be delayed for the Central Time Zone, meaning it would start at 9pm Central.

While verifying this online, I came upon an interesting Reddit thread that asked, “Americans, what does 10/9c mean?” These comments were of note.

10/9c means 10 est (eastern) 9cst…

Actually 10/9C means the show is on at 10 in all american timezones except central. I really don’t know why they do it but basically Central gets all of their TV an hour earlier than the rest of us.

There was much discussion about this, and a lot of down-voting on comments as people strongly disagreed with each other’s viewpoints.

What is not true about it? Being in Pacific Time I know when a network add says it will be on at 10, 9 Central that it is going to be on at 10 in Pacific time.

The only exception I have ever seen to this is AMC, the walking dead airs at 6PM Pacific (Only on Dish, Comcast it is on at 9PM)

Yesterday, I asked of my Facebook friends – what does the value “10/9c” mean with show programming? Some people suggested that it clearly means 10pm EST. But does it? It was clear to two different people over the age of 50. I thought it meant 10pm in all time zones. It wasn’t as clear to anyone.

Why would anyone be vague in advertisement material? That seems like a waste of time and money unless there were no alternative. My objection, the thing that started this research, was to that ambiguity.

Why put 10/9c in advertising when you can put 10pm EST? Or shorten it to 10EST, which is technically exactly the same number of characters in case brevity was the concern. Much of our entertainment is online the days, so a viewer could potentially be anywhere in the world. The person who made the original Reddit post above lived in Norway. No one should have to do any sort of research if advertising is done correctly.

I looked for present-day, practical examples. I looked at schedules for CNN, Fox, and the PGA Tour. I determined that the time zone noted seemed to depend on the broadcast location, but it is not noted as 10/9c. The time zones are noted.

What was the history and reasoning behind using 10/9c in the first place?

The Wikipedia page on the Effects of Time Zones on North America Broadcasting indicated the following.

“Effectively, the East, Mountain and West network feeds allow prime time on broadcast television networks to end at 10:00 p.m. Central and Mountain and 11:00 p.m. Eastern and Pacific. When it first expanded its programming into prime time in April 1987, Fox became the first major broadcast network in the U.S. to offer a “common prime” schedule; this type of scheduling subtracts an hour from the prime time schedule, reducing it to two hours on Monday through Saturdays and three hours on Sundays – ending evening network programming earlier than NBC, CBS and ABC did – and continue to do (Fox did expand its Sunday primetime schedule into the 10:00 p.m. timeslot in September 1987, before giving back that hour to its stations in September 1993). The WB and UPN followed the “common prime” scheduling model when they both launched in January 1995; the replacements for those networks, The CW and the MyNetworkTV program service, similarly used that model upon their launches in September 2006.”

“Subscribers to cable or satellite television services may still only receive East Coast feeds for certain channels even if they reside on the West Coast. Some cable channels only offer one broadcast feed, where viewers see the same program in all time zones. “

Comments and Conclusions

I did not identify an accepted or expected guideline for programming time listings. The schedules I found for present day broadcasting listed the time zone where the show was being broadcast. An actual convention may exist, but I did not identify one. Regardless, the fact that there is any question, any lack of clarity, strengthens my suggestion to use time zones in all advertising material.