Add or Edit Phone Number Normalization Rule

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Use the Add Phone Number Normalization Rule dialog box to create a phone number normalization rule. Use the Edit Phone Number Normalization Rule dialog box to modify a phone number normalization rule.


Specify a name for this normalization rule. The name must be a Unicode string that does not exceed 256 characters. The name should clearly identify the normalization rule.

Copy rule

Click to use an existing normalization rule as the template for a new rule.


Specify a description for the normalization rule. The description can be any Unicode string of up to 1,024 characters. The description provides an opportunity to describe the normalization rule more fully.


Specify the regular expressions for the phone pattern and translation pattern.

Phone pattern regular expression

Specify a .NET regular expression that describes the numeric pattern of the user-supplied phone numbers that is to be matched.

Translation pattern regular expression

Specify the E.164 format into which phone numbers matching the Phone pattern regular expression are to be translated. For example, you could specify a phone pattern of ^([0-9]{7})$ and a translation pattern of +1425$1 to translate a number such as 5550123 to +14255550123.

Internal enterprise extension

Select this check box if the normalization rule results in a phone number that is internal to the enterprise.

Use translation when dialing from device

Select this check box if you want to translate numbers dialed from a device.

Launch guide

Click to access a guide to creating common phone number translations.

Test translation

Use to test the specified translation regular expressions.

Sample dialed number

Specify a sample dialed number.

Translated number

If the sample dialed number you specify matches the phone pattern you specified, the translated number is displayed.

Learn More Online

Click to expand or collapse

Each location profile must have at least one normalization rule. The normalization rules define how phone numbers expressed in various formats are routed for the named location by specifying how to convert dialed numbers in various formats to the standard E.164 format for purposes of reverse number lookup. The same number string may be interpreted and translated differently depending on the locale from which it is dialed. Normalizing user-supplied phone numbers provides a consistent format that facilitates matching a dialed number to the intended recipients SIP-URI, as well as applying dialing authorization rules to the calling party.

A normalization rule needs to account for the following number fields:

  • Dial plan

  • Country code

  • Area code

  • Length of extension

  • Site prefix

You create normalization rules using .NET Regular Expressions. The Launch Guide button provides access to additional information about how to create .NET Regular Expressions. For details about using .NET Regular Expressions to specify a phone usage normalization rule, including examples, see the Office Communications Server Technical Library.

You cannot assign a single phone number normalization rule to multiple location profiles. Instead, you create a separate normalization rule for each location profile. To facilitate the process of specifying each normalization rule, you can copy an existing normalization rule. When you copy a normalization rule, the existing rule is used as a template for the creation of the new normalization rule. You must specify a new and unique name for the new normalization rule. If required, you can also modify any of the copied settings, as appropriate to the location.

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