To ensure you can configure the routing settings in your telephone system correctly, you need to know the format in which your telephone number is signalled.

In my.easybell, you can choose between two different modes, which we’ll briefly explain here:

1. the E.164 format

Standard for pool accounts and direct extensions from number blocks

In the E.164 format, the international dialling code is specified without leading zeros (e.g. 413012345).

If you use the E.164 format, the call signalling information is taken from the SIP Invite. There, the full dialled number is stored in the TO: header in E.164 format, i.e. without leading zeros.

This setting is easier for most telephone systems to process and allows for more accurate routing than, for example, the international format.

2. the E.164 format with leading "+"

Standard for 3CX telephone systems

Some telephone systems, including 3CX, require signalling in E.164 format with a leading plus sign.

Similar to the E.164 standard without a plus sign, the information for call number signalling is taken from the SIP Invite.

Switching the phone number format

You can customize the number format for each phone number or trunk individually. This is done as usual in call number management.

Detailed instructions can be found here: "Adjusting call number signaling for incoming calls".

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Created on: 22. June 2026