# 18 E164 Number Processing
E.164 is an [international standard](https://en.wikipedia.org/wiki/International_standard) ([ITU-T](https://en.wikipedia.org/wiki/ITU-T) Recommendation), titled *The international public telecommunication numbering plan*, that defines a [numbering plan](https://en.wikipedia.org/wiki/Telephone_numbering_plan) for the worldwide [public switched telephone network](https://en.wikipedia.org/wiki/Public_switched_telephone_network) (PSTN) and some other data [networks](https://en.wikipedia.org/wiki/Telecommunications_network).
E.164 defines a general format for international [telephone numbers](https://en.wikipedia.org/wiki/Telephone_number). Plan-conforming telephone numbers are limited to only digits and to a maximum of fifteen digits.[\[1\]](https://en.wikipedia.org/wiki/E.164#cite_note-:0-1) The specification divides the digit string into a country code of one to three digits, and the subscriber telephone number of a maximum of twelve digits.
In PortSIP PBX, E164 processing converts user-dialed numbers (including those with a leading +) into a standardized format that can be interpreted by your outbound rules and provider.
Using E164 processing is optional, but it can help solve the issue of handling numbers dialed with a leading +. It converts these numbers into a format that can be interpreted by the rules based on the call type (local, national, or international).
***
### E.164 Settings
The **E.164 Settings** control how PortSIP PBX normalizes and transforms dialed phone numbers—especially numbers entered in international (E.164) format—before outbound routing rules are applied.
#### Accessing E.164 Settings
1. Sign in to the PortSIP PBX Web Portal as a **Tenant Admin**.
2. Navigate to **Blacklist and Codes > Codes and E164 > E164**.
3. The E.164 configuration page appears (as shown in the screenshot below).
***
### Configuration Options
#### International Code
Defines the international dialing prefix used when placing calls to other countries **without using the “+” symbol**.
* Example (United States):
* International Code: `011`
* Dialed number: `+44123456789`
* Converted number: `01144123456789`
This allows users to dial international numbers using E.164 format while remaining compatible with carriers that require a numeric international prefix.
***
#### Process E.164 Numbers
Controls whether the PBX processes numbers that begin with a leading **“+”**.
* **Enabled**:\
Numbers dialed in E.164 format (e.g., `+44123456789`) are normalized according to the E.164 rules.
* **Disabled**:\
The PBX does **not** modify the dialed number, even if it starts with `+`.
> **Recommendation:**\
> Enable this option in most deployments to ensure consistent number normalization.
***
#### Remove Special Characters
**Remove the following characters from processed numbers:**\
`(`, `)`, and spaces
* When enabled, the PBX removes these characters from dialed numbers.
* Example:
* Dialed number: `+1 (813) 456 78910`
* Converted number: `+181345678910`
This ensures compatibility with SIP trunks and outbound routing rules.
***
#### Remove Country Code for Same Country
When enabled, the PBX removes the country code if the call is made **within the same country**.
* Example (United States):
* Dialed number: `+12345678910`
* Converted number: `2345678910`
This is useful when your carrier expects national-format numbers for domestic calls.
***
#### Select Country
Select the country where your PBX tenant is located.
* This setting allows the PBX to correctly identify:
* Your country code
* Domestic vs. international calls
**Example:**\
Select **United States (US)** for all examples in this section.
***
#### Area Code
Enter your local area code.
**Remove if Same Area Code**
When enabled, the PBX removes the area code for local calls if it matches the configured area code.
* Example:
* Area Code: `813`
* Dialed number: `+181345678910`
* Converted number: `45678910`
This is useful in regions where local dialing does not require an area code.
***
#### National Code
Adds a national dialing prefix to the beginning of the number during processing.
* Example:
* National Code: `8`
* Dialed number: `+12345678910`
* Converted number: `82345678910`
This is typically required in countries where domestic calls must include a national prefix.
***
#### Add Prefix
Adds a custom prefix to the processed number.
* Common use cases:
* Selecting specific outbound rules
* Carrier-specific routing requirements
> **Important:**\
> E.164 rules are processed **before outbound routing rules**.
* Example:
* Prefix: `2`
* Dialed number: `+12345678910`
* Converted number: `22345678910`
***
### Non-E.164 Calls
A **Non-E.164 call** is a call dialed **without a leading “+”**.
#### International Calls (Non-E.164 Format)
If the dialed number:
* Does **not** begin with `+`, and
* Begins with the configured **International Code**
then the call is treated as an **international call**.
**Call Processing Flow**
1. The PBX identifies the call as international based on the **International Code**.
2. The PBX checks the destination country code against:
* **Blacklist**
* **Codes > Codes and E164 > Allowed Country Code**
3. The PBX verifies the caller’s **role and permissions**:
* If the caller does **not** have permission to make international calls, the call is rejected.
**Example**
* International Code: `00`
* Dialed number: `004412345678`
* Extracted country code: `44` (United Kingdom)
The PBX will:
* Verify whether country code `44` is allowed
* Check whether the caller is permitted to place international calls
If either check fails, the call is blocked.
***
#### Domestic Calls (Non-E.164 Format)
If the dialed number:
* Does **not** begin with `+`, and
* Does **not** begin with the International Code
then the call is treated as a **domestic call**.
The PBX checks:
* The caller’s role and permissions for domestic calling
If the caller is not authorized to place domestic calls, the call is rejected.
***
### E.164 Calls
An **E.164 call** is any call where the dialed number begins with a leading **“+”**.\
These calls are always treated as **international-format numbers**, but how they are processed depends on whether **Process E.164 Numbers** is enabled.
***
### When **Process E.164 Numbers** Is Disabled
If **Process E.164 Numbers** is disabled, the PBX does **not** normalize or rewrite the dialed number.
#### Call Processing Behavior
1. The call is identified as an **international call**.
2. The PBX checks the destination country code against:
* **Blacklist**
* **Codes > Codes and E164 > Allowed Country Code**
3. The PBX verifies the caller’s **role and permissions**:
* If the caller is not permitted to make international calls, the call is rejected.
#### Example
* Dialed number: `+4412345678`
* Country code extracted: `44`
The PBX checks whether country code **44** is allowed and whether the caller has international calling permissions.\
If either check fails, the call is blocked.
***
### When **Process E.164 Numbers** Is Enabled
When enabled, the PBX **removes the leading “+”** and applies E.164 normalization rules before outbound routing.
After removing the `+`, the PBX evaluates the number using the following logic.
***
#### 1. Dialed Number Starts with the **Selected Country Code**
If the dialed number begins with the configured **Select Country** code, the call is treated as a **national (domestic) call**.
**Processing Steps**
1. Remove the leading `+`.
2. Remove the country code.
3. If **Remove if same country** is enabled, the country code is discarded.
4. If **Remove Area Code** is enabled, the area code is also removed.
5. Generate the new dialed number using the rule:
```
Prefix + National Code + Remaining Number
```
6. Check the caller’s **domestic calling permissions**.
* If the caller is not permitted to make domestic calls, the call is rejected.
**Example**
Configuration:
* Select Country: `44`
* Area Code: `31`
* Remove if same country: **Enabled**
* Remove Area Code: **Enabled**
* National Code: `11`
* Add Prefix: `22`
Dialed number:
```
+4431867762
```
Processing result:
* Remove `+` → `4431867762`
* Remove country code `44` → `31867762`
* Remove area code `31` → `867762`
* Add National Code `11` → `11867762`
* Add Prefix `22` → `2211867762`
**Final dialed number:** `2211867762`
***
#### 2. Dialed Number Does NOT Start with the Selected Country Code
If the E.164 number does **not** begin with the configured country code, the PBX treats it as an **international destination**.
**Processing Steps**
1. Remove the leading `+`.
2. Generate the new dialed number using the rule:
```
Prefix + International Code + Dialed Number
```
3. Determine call type:
* If **Add Prefix** is empty → **International call**
* If **Add Prefix** is configured → **National call**
4. For international calls:
* Check **Allowed Country Code**
* Check caller’s **international calling permissions**
If any check fails, the call is rejected.
**Example**
* International Code: `00`
* Add Prefix: *(empty)*
* Dialed number: `+3312345678`
Processing result:
* Converted number: `003312345678`
* Country code checked: `33`
The PBX verifies:
* Country code `33` is allowed
* Caller has international calling permissions
If either condition fails, the call is blocked.
***
### Summary: E.164 Call Processing Logic
| Scenario | Call Type | Permission Check |
| ------------------------------- | ------------- | ---------------- |
| `+` dialed, processing disabled | International | International |
| `+` dialed, same country | Domestic | Domestic |
| `+` dialed, different country | International | International |
| Prefix added | National | Domestic |
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