# U.S cell phone numbers **URL:** \ **Category:** Factual Questions\ **Created:** [May 7, 2014, 12:54am UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860 "2014-05-07T00:54:59Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![EndlessEntropy](https://avatars.discourse-cdn.com/v4/letter/e/f9ae1b/32.png) [@EndlessEntropy](https://boards.straightdope.com/u/EndlessEntropy)\ **Post date:** [May 7, 2014, 12:54am UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/1 "2014-05-07T00:54:59Z")
Can cell phone numbers in the U.S, if 10 digit, be preceded by 5? I copied down a cell phone number for a friend but I think I may have got it wrong, it’s 11 digits and the first number is 5 and doesn’t seem right. I’ve just only see 11 digit numbers with "1"as the first number like 1-xxx-xxx-xxxx but never 5-xxx-xxx-xxxx ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [May 7, 2014, 1:05am UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/2 "2014-05-07T01:05:36Z")
First of all, the “1” is not part of the number, but an access code that tells the system to expect a long-distance (10 digit) number to follow. So, no, “5” is not a valid prefix whether the recipient is landline or cellphone. And there is no difference between landline and cellphone (numbering) anymore. ---
**Author:** ![EndlessEntropy](https://avatars.discourse-cdn.com/v4/letter/e/f9ae1b/32.png) [@EndlessEntropy](https://boards.straightdope.com/u/EndlessEntropy)\ **Post date:** [May 7, 2014, 1:14am UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/3 "2014-05-07T01:14:30Z")
Yeah I did add an extra number somewhere… thanks! ---
**Author:** ![Mr\_Downtown](https://avatars.discourse-cdn.com/v4/letter/m/8e8cbc/32.png) [@Mr\_Downtown](https://boards.straightdope.com/u/Mr_Downtown)\ **Post date:** [May 7, 2014, 3:50am UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/4 "2014-05-07T03:50:21Z")
Technically, the 1 isn’t an access code. It’s the country code for US & Canada. On most cell phones you only need to dial the 10 digits, because there’s no need to tell a billing computer that you’re calling _long distance._ ---
**Author:** ![Pai325](https://avatars.discourse-cdn.com/v4/letter/p/c68b51/32.png) [@Pai325](https://boards.straightdope.com/u/Pai325)\ **Post date:** [May 7, 2014, 5:17am UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/5 "2014-05-07T05:17:34Z")
> [@Mr\_Downtown](#): > > Technically, the 1 isn’t an access code. It’s the country code for US & Canada. > > On most cell phones you only need to dial the 10 digits, because there’s no need to tell a billing computer that you’re calling _long distance._ My phone requires me to dial 1 if I dial a number outside of my area code. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [May 7, 2014, 5:30am UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/6 "2014-05-07T05:30:23Z")
> [@Pai325](#): > > My phone requires me to dial 1 if I dial a number outside of my area code. In some locations, it’s required. Here, in the Chicago area, dialing the area code–even if it’s the same as yours–has been required since late 2009. ---
**Author:** ![cochrane](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cochrane/32/10441_2.png) [@cochrane](https://boards.straightdope.com/u/cochrane)\ **Post date:** [May 7, 2014, 5:36am UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/7 "2014-05-07T05:36:07Z")
> [@Mr\_Downtown](#): > > Technically, the 1 isn’t an access code. It’s the country code for US & Canada. > > On most cell phones you only need to dial the 10 digits, because there’s no need to tell a billing computer that you’re calling _long distance._ I was not aware of that. I’ve been accustomed to dialing 1 before any long distance number. Just now I dialed my bank’s 800 number without prefacing it with the 1 and the call went right through. Now I’ll know to drop the 1 from now on. ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [May 7, 2014, 1:46pm UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/8 "2014-05-07T13:46:25Z")
> [@Mr\_Downtown](#): > > Technically, the 1 isn’t an access code. It’s the country code for US & Canada. > > On most cell phones you only need to dial the 10 digits, because there’s no need to tell a billing computer that you’re calling _long distance._ The “1” prefix was instituted some years ago, before cellphones were common (or even existed). It was necessary due to the switching concept instituted in the 1950’s for long distance. At that time, the switching (non-computerized) used the 2nd digit dialed to determine what to expect next: if the 2nd digit was 0 or 1, 8 digits followed (long distance, 10 digits total); if the 2nd digit was not 0 or 1, 5 digits followed (local, 7 digits total). This concept only allowed a limited number of areas codes, and they were running out of assignable codes. By prefixing “1” to the string of 10 digits, they no longer were limited to area codes with only 0 or 1 as the middle digit. You may think of “1” as a country code, but that was not the original idea. Cellphones nowdays seem to be smart enough to tell 10 digit numbers apart from 7 digit ones, and I think they may automatically prefix a “1” if you forget to put it in. Landline phones, since they are largely emulating old-style stupid phones, may not do so. ---
**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\ **Post date:** [May 7, 2014, 3:19pm UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/9 "2014-05-07T15:19:26Z")
> [@Musicat](#): > > old-style stupid phones, I say a comment in my paper today which referred to phones that were not ‘smart’ as ‘thickphones’ - I can see that catching on. ---
**Author:** ![Cayuga](https://avatars.discourse-cdn.com/v4/letter/c/3e96dc/32.png) [@Cayuga](https://boards.straightdope.com/u/Cayuga)\ **Post date:** [May 7, 2014, 5:26pm UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/10 "2014-05-07T17:26:04Z")
> [@bob\_2](#): > > I say a comment in my paper today which referred to phones that were not ‘smart’ as ‘thickphones’ - I can see that catching on. Are you in the UK? I don’t think I’ve ever heard an American use _thick_ to mean “stupid.” ---
**Author:** ![Cayuga](https://avatars.discourse-cdn.com/v4/letter/c/3e96dc/32.png) [@Cayuga](https://boards.straightdope.com/u/Cayuga)\ **Post date:** [May 7, 2014, 8:00pm UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/11 "2014-05-07T20:00:51Z")
ETA: I’ve been hearing “dumb phone” over here for a few months. Pretty sure it’ll be common soon, if it isn’t already. ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [May 7, 2014, 8:09pm UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/12 "2014-05-07T20:09:27Z")
> [@Cayuga](#): > > Are you in the UK? I don’t think I’ve ever heard an American use _thick_ to mean “stupid.” As an American, I can say that “thick” has been used to mean “stupid,” at least in the days when “retarded” was acceptable speech in public. ---
**Author:** ![OldGuy](https://avatars.discourse-cdn.com/v4/letter/o/3bc359/32.png) [@OldGuy](https://boards.straightdope.com/u/OldGuy)\ **Post date:** [May 7, 2014, 8:21pm UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/13 "2014-05-07T20:21:11Z")
> [@Musicat](#): > > Cellphones nowdays seem to be smart enough to tell 10 digit numbers apart from 7 digit ones, and I think they may automatically prefix a “1” if you forget to put it in. Landline phones, since they are largely emulating old-style stupid phones, may not do so. It seems to me it’s not really a question of smart or not it’s what extra button you have to push. On landlines you push 1 first, on cell phones you push “send” last. The cell phone isn’t smart enough to distinguish 7 from 10 digits, it’s simply smart enough to know when you push “send” that that’s all the numbers you’re going to enter. ---
**Author:** ![gazpacho](https://avatars.discourse-cdn.com/v4/letter/g/6f9a4e/32.png) [@gazpacho](https://boards.straightdope.com/u/gazpacho)\ **Post date:** [May 7, 2014, 8:46pm UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/14 "2014-05-07T20:46:45Z")
It is not so much that the cell phone is smart it is what the cell phone connects to that is smart. In some areas with a land line phone you can dial 7 digits and be put through to numbers with your area code. In other places you need to use all 10 digits. A few years back (10 or so) I was in Hawaii with my cell phone and I had to manually enter people’s phone numbers proceeded by 1 because the contacts on the phone did not include the 1. The contacts all worked back home on the mainland. Subsequent visits to Hawaii no longer had issues with needing a 1 in front of peoples numbers. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [May 7, 2014, 9:14pm UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/15 "2014-05-07T21:14:45Z")
> [@Cayuga](#): > > Are you in the UK? I don’t think I’ve ever heard an American use _thick_ to mean “stupid.” Oh, it’s definitely used in US English, as in, “Jesus, how fucking thick are you?” or “Whaddareya, fucking _thick_?” That said, it doesn’t work for me in the opposite of smartphone context. “Dumbphone” would be the more natural one. “Thickphone” would take me a few cycles of brainpower to understand that “thick” is being used in the “dumb” sense, rather than the “opposite of thin” sense. ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [May 8, 2014, 5:20am UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/16 "2014-05-08T05:20:06Z")
In the mid-1970’s in Livermore, Ca., when that “1” prefix was still rather new, the local phone company (AT&T or Bell or whatever it was called then) kept changing their mind about whether long-distance calls needed to have it. Every few months, for a while, they would send another notice along with the bill, changing the rule. Eventually they settled on having it be optional, for a while. At the time, all area codes still had 0 or 1 in the middle, but they were trying to plan ahead and apparently having a hard time with that. ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [May 8, 2014, 6:04am UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/17 "2014-05-08T06:04:48Z")
Yeah, 1 and 0 are the trunk dialling digits for use within the North American Numbering Plan (NANP), the telephone numbering plan shared by Canada, the USA, and certain other countries. 1 also happens to be the country code for the NANP, used when calling from outside the NANP. Thus, a number can validly be written as 1-xxx-xxx-xxxx for calling within the NANP or +1 xxx xxx xxxx for calling from outside the NANP. This is different from, say, the UK, where a number dialled domestically as 020-xxxx-xxxx is dialled internationally as +44 20 xxxx xxxx. The UK trunk dialling digit 0 is different from the UK country code 44. I did not know this until studying the phone system in electronics school. ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [May 8, 2014, 6:13am UTC](https://boards.straightdope.com/t/u-s-cell-phone-numbers/687860/18 "2014-05-08T06:13:22Z")
And dialling strategies differ across the NANP. Some places, you have to dial a 1 or 0 before all long-distance call. Other places, you have to dial a 1 or 0 before all area codes, long-distance call or not. Some areas require area codes on all calls, local or not, and if the “dial 1 or 0 before an area code” rule is in effect, a 1 or 0 must be dialled before all calls. Some places do not allow 1 before local calls. And as others have mentioned, some phone companies allow all calls to be dialled without a 1 before. It’s inconsistent.