What is the best format for a full 10-digit U.S. phone number in terms of readability, accessibility, and overall ease-of-use?

A few examples:

  • (800) 555-1234
  • (800)555-1234 (no space after the area code)
  • 800-555-1234
  • 800 555-1234

Personally I think the first option is best but I can't pinpoint why. I also wonder whether the inclusion of the parentheses adds helpful cues or causes cognitive overload and/or distraction.

The target audience is the general public and the users are almost all American residents. The phone numbers are normally displayed on a web site alongside other data such as a street address.

Many of these numbers were entered by the user and are being displayed back for verification purposes. The users are allowed to enter the number in any format; on the server, we strip all spaces and punctuation and store only the 10 digits.

  • 2
    This may not be relevant to your application but your examples don't have the 'trunk prefix' which would be something like 1- (800)-555-1234. If users are doing the phone entry you might want to watch out for that. en.wikipedia.org/wiki/Trunk_prefix
    – jmathew
    Commented Apr 18, 2016 at 17:54
  • 3
    In some applications, such as resume headings, alternative formatting such as 860.740.4500 is easier to read. Commented Apr 18, 2016 at 19:25
  • 8
    Avoid the debate entirely and use the standard way.
    – user207421
    Commented Apr 19, 2016 at 0:34
  • 4
    @user1717828 I don't actually find that easier to read... At a glance, it's nearly identical to an IP address. I know you said "in some applications", but I personally dislike when people try to make a phone number look hip or trendy. Clarity should always trump style.
    – Lindsey D
    Commented Apr 19, 2016 at 0:35
  • 5
    @EJP That article says The traditional formatting convention for phone numbers is (NPA) NXX-XXXX but the format can be written NPA-NXX-XXXX, or as 1-NPA-NXX-XXXX and Sometimes the stylized format NPA.NXX.XXXX is seen. So basically that link says "do whatever you want"
    – Brad
    Commented Apr 19, 2016 at 13:15

5 Answers 5


I agree with you that the first is best.

Good UX is largely about reducing the cognitive load of a user. (###) ###-#### is a format that, in North America, is unique to phone numbers, so I know as soon as I see the format that this is a phone number.

At first glance, if I just see {several numbers} {hyphen} {several numbers}... well, this could be a social security number, postal code, credit card number, phone number, etc. It would make me have to inspect the format closer, read a label, or evaluate the context in which the number is being displayed to determine its meaning.

Remove as much cognitive load from the user as possible.

Use the visually distinctive (###) ###-#### format.

  • 13
    Also, Canadian numbers and Mexican numbers Commented Apr 18, 2016 at 14:51
  • 5
    Sorry if I offended you, Canadian Luke! Commented Apr 18, 2016 at 15:02
  • 5
    It wasn't something I took offence to, we just like being thorough on Stack Exchange Commented Apr 18, 2016 at 15:03
  • 5
    I've come to dislike using parentheses around area codes. It made sense when the way phone numbers were used was typically to dial only the exchange code and subscriber number, and "long distance" calls (between different area codes) required a special "escape code" prefix followed by the area code. Now that the digit groups (within a country) always all appear together, marking that one group as distinct seems archaic. I almost never have any trouble distinguishing phone numbers, SSNs, zip codes, credit card numbers, software registration codes, GPS coordinates, UUIDs, etc. Commented Apr 18, 2016 at 15:56
  • 2
    @Polyergic: I suggest that you describe as "was typically" is in fact "is typical" for most people, most of the time. And so the conventional (xxx) xxx-xxxx works perfectly well, far better than the annoying xxx.xxx.xxxx which I always see as an internet address at first glance.
    – jamesqf
    Commented Apr 18, 2016 at 16:53

Although option 1 is used most often, I would argue that

  • the concept of an "area code" is pretty much deprecated by cell phones. Now we simply have 10-digit phone numbers.

  • many areas of the United States (and, I'm pretty sure, all cell phones) mandate 10-digit dialing, so the idea that the first three digits might be optional is also outdated.

For these two reasons, I would go for option 3, 800-555-1212, as the forward-looking choice for displaying a phone number.

  • 5
    The second point is not true in general, though it might (appear to) be of large urban areas that have several area codes (overlays, in telephone parlance). I can dial any number in my area code (which covers most of one of the larger US states) from my cell phone using 7 digits - including, interestingly enough, my former neighbors who now live in a neighboring state, but kept their old phone numbers.
    – jamesqf
    Commented Apr 18, 2016 at 19:46
  • 1
    I honestly don't know. My area requires 10-digit dialing, and my cell phone requires 10-digit dialing. I know that cell phones emphatically do not use 1- before the area code. I thought that, for that reason, cell phones require 10-digit dialing.
    – hymie
    Commented Apr 18, 2016 at 19:51
  • 6
    Every few months, I get a call from this elderly lady on her land-line, attempting to call her financial institution's toll-free number, 877-ABC-DEFG. My phone number is (XYZ) 877-ABCD, and XYZ is also her area code; I have to remind her each time that she needs to dial 1 first. Based on this, I would recommend either Option 1, or 1-800-555-1212 as an alternative form of Option 3, if that is preferred over the uses of parentheses. Commented Apr 18, 2016 at 22:19
  • 3
    "The first three digits of your 10-digit cell phone number indicates where you lived in 2007." Commented Apr 19, 2016 at 1:35
  • 1
    It really is just a 10-digit code now. I'm in Oregon where one code covers more than half the state. You still have to specify the code because there are so many out of state cell users. The parenthetical notation is a relic of bygone days. Commented Apr 19, 2016 at 16:13

I would suggest using the E.123 number unless your audience is purely USA based. That way, us poor internationals don't have to guess about how to call a number.

+1 800 555 1234 since then it'll work on every phone, worldwide*


Bitter experience of working for multiple USA based companies who have large address Exchange address books of pure 'USA' numbers... a joy.

(* assuming it can dial a +, of course. Welcome to the 21st century.)

  • 4
    +1 for the +1 (haha). as an ignorant american who has never needed to place an international call, i've always wondered whether the plus sign needed to be dialed or whether it's strictly decorational (like the parentheses in domestic numbers). Commented Apr 19, 2016 at 22:03
  • Given my engineer-mindset, I'm certainly in favour of this format, however, one has to note that many people sadly have no idea how to enter the "+" on their phone...
    – jcaron
    Commented Apr 20, 2016 at 11:23
  • @WoodrowBarlow. The "+1" means "whatever your country uses to indicate that you're making an international call". For most countries, that's 00. The North American Numbering plan (USA, Canada, Mexico, ...) uses 001, for some reason.
    – TRiG
    Commented Apr 20, 2016 at 14:10
  • On a mobile phone, which is what most people are using these days, just holding the 0 key for about 2 seconds puts the + in for you. @TRiG is right, the 00 / 001 is another half standard that most countries did one way but others did differently. Sigh... Another advantage of putting all your numbers in your own address book with the + is that when you travel, you can still call people without having to figure out what the local country calling conventions are. Commented Apr 21, 2016 at 6:45
  • I believe that France originally used 19. They've now switched to 00, but I think 19 still works. @PaulHargreaves.
    – TRiG
    Commented Apr 21, 2016 at 8:31

Option 1 has the following characteristics, making it the preferred choice:

It's Conventional

The Wikipedia page for "National conventions for writing telephone numbers" states:

The traditional formatting convention for phone numbers is (NPA) NXX-XXXX, where NPA is the area code and NXX-XXXX is the subscriber number

This is probably why you feel it's the right choice - you see it everywhere.

It's readable

Is it any more readable than options 3 or 4? That's arguable, but the ease with with Option 1 can be scanned/parsed, combined with it's conventionality, make it the right option to go with.

There are lots of ways you can play with the the styling of a telephone number, but my advice here is that when you've got a strong and functional convention, don't mess with it.


When in doubt go to the bible of all publishing; the U.S. Government style manual. This is used by all (almost all) publishers, and is the basis for all printing in the U.S. They show a format of 555-555-5555.

Usually in programming an input form, it will show (555)555-5555 to make it easier to enter the numbers. I prefer this on all business cards and forms.

Ref: https://www.govinfo.gov/content/pkg/GPO-STYLEMANUAL-2016/pdf/GPO-STYLEMANUAL-2016.pdf

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.