Standard format for phone numbers? [closed]

Inside the USA, in business contexts, "(310) 555-1212" is fairly standard. However, it's not very computer-friendly; also, due to area code overlays in a growing number of areas of the US, you must often dial a 1 before the area code in any case, so "1-310-555-1212" is becoming fairly common (on the business cards of people who are more practical than formal, for example.) "310.555.1212" is also common on modern business cards and letterheads.

In international (and Internet telephony) contexts, you should specify a telephone number according to the ITU E.123 standard: the above number (Information in Los Angeles, CA, USA) would be "+1 310 555 1212".

  • "+"
  • the national code (1 for the USA)
  • space
  • the area/regional code
  • space
  • the local exchange
  • space
  • the local number

Unfortunately, I don't know the local/national conventions (for business cards, letterhead, correspondence, scrawling your number on a napkin at a bar, etc.) in any country but the US.

Note: The "(310) 555-1212" format is what I was taught in typing class (does anyone still take typing class?) in high school in the 1980s; it's still widely used in the US - for example, roadside billboards almost always use this format (unless the telephone number spells a word or phrase, as in "1-800-I FLY SWA" for Southwest Airlines.) It has the advantage of being instantly recognizable (in the US, anyway) as a telephone number; most of the other formats can be a bit ambiguous if seen without context. However, as noted above, I believe this format is slowly going out of fashion.


This is I think borderline on topic, though it is not really language related. In terms of standards and recommendations you can start with wikipedia article on telephone number which will lead you to

  • ITU's recommendations, which are international

It specifies the following formats

+22 607 123 4567
(0607) 123 4567

to distinguish international (first form) from national (second format), but I often see them merged as

+22 (607) 123 4567

(which assumes that person calling within the country will know that country code +22, usually dialed as 0022 needs to be stripped and 0 needs to be prepended to 607)

If you are interested in particular country try to look for official standards in the country (usually national telecom would have those).


Just to confuse matters most UK area codes begin with a 0 but you drop the zero if dialing from outside the country so it's

+44 (0) 1223 456789

Meaning dial 456789 from the same area code, 01223 456789 from in the UK and +44 1223 456789 from abroad.