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Cisco - International Dialing

Your Cisco services are designed setup to send and receive all calls to carriers in the ITU (International Telecommunications Union) E.164 + format. This format is the internationally-standardized format for all phone numbers globally. 
E.164 + numbers can have a maximum of fifteen digits and are written as follows: 
[+][country code][subscriber number including area code]. 
Some carriers do not send or receive in E.164 +. If this is the case it will require approval by CCE as work will need to be done to convert digits to the carrier’s accepted format.
For example, to convert a US phone number (555) 234-5678 to E.164 + format, one would need to add the ‘+’ prefix and the country code (which is 1 in the US) in front of the number. This would translate to +15552345678. 
In the UK and many other countries internationally, local dialing requires the addition of a 0 in front of the subscriber (or telephone) number. However, to use E.164 + formatting, this 0 must be removed. A number such as 020 1234 5678 in the UK (including the country code) would translate to +442012345678.
For placing outbound calls from the Cisco Platform, the conversion to E.164 + in most cases is handled by Cisco Unified Call Manager via “Dial Plans”. There are currently dial plans for the following countries. 
Note that we are not limited to just the below countries. Any country can be supported as long the E.164 format is accepted and followed. Countries are listed with their Country Codes.

  1. United States (+1) (This includes any Country that follows the ‘North American Numbering Plan’. There are currently 25 countries and territories that follow this format)
  2. Mexico (+52)
  3. United Kingdom (+44)
  4. Australia (+61)
  5. Hong Kong (+852)

When dialing out from any country you will need to know the “International Prefix Code” for that region. This is the code that prepends the “Country Code” and “Subscribers Number” or “Destination Telephone Number”. This format would be written as follows: [OU prepend digit][international prefix code][country code][subscriber number].
For example, if you were placing a call to the UK number above from your Cisco phone that is located in the United States, you would dial 8 [OU prepend digit] + 011 [international prefix code for U.S.] + 44 [country code] + 2012345678 [subscriber number]. 
This format can be followed when dialing out from any of the countries above that we currently have supported dial plans for. 
The ITU (International Telecommunication Union) recommends the sequence 00 as a standard for an international call prefix, and this has been implemented by many countries, but not all of them.Below are the same countries with their International Prefix Code. 

  1. United States (011)
  2. Mexico (00)
  3. United Kingdom (00)
  4. Australia (0011)
  5. Hong Kong (001)