Connecting SIP Trunk to Bitrix24
A SIP trunk is a virtual communication channel between Bitrix24 and a phone operator. Through it, calls from an existing company number arrive in Bitrix24, and outgoing calls are placed through the operator at favorable rates. Unlike renting a number from Bitrix24, a trunk allows you to keep an existing number and not overpay for calls.
What is SIP trunk technically
A trunk is a set of SIP credentials that the provider issues for PBX registration. Credentials consist of:
-
SIP server address of the provider (host) — for example,
sip.provider.ruor IP address. - Login and password — for registration on the provider's server.
- Phone number — which will be displayed for outgoing calls (CallerID).
Bitrix24 registers on the provider's server as a SIP device and accepts incoming calls addressed to this number.
Configuring trunk in Bitrix24
Section: CRM → Telephony → Settings → Add number → Connect your number (SIP).
Parameters to fill in:
| Parameter | Description |
|---|---|
| Server | SIP server address of the provider |
| Login | SIP login of the trunk account |
| Password | SIP password |
| Outgoing number | Number for CallerID |
| Transport | UDP (by default) or TCP/TLS |
After saving, Bitrix24 attempts to register on the SIP server. Registration status is displayed in the "Trunks" section — a green circle means successful connection.
Specifics of working behind NAT
Most SIP trunk issues arise from NAT — when Bitrix24 runs on a server behind a router or in the cloud with changing external IP. Symptoms: registration passed but calls don't arrive or no sound.
The solution depends on the side:
- If trunk is with cloud Bitrix24 — NAT problems are rare, Bitrix servers have public IPs.
-
If using your own Bitrix24 box — in SIP server settings, you need to specify external IP (
externalipin Asterisk if used as intermediary) or configure STUN. - On the router side — open ports: TCP/UDP 5060 (SIP), UDP 10000-20000 (RTP media stream).
Incoming call routing setup
After registering the trunk, configure incoming processing: in what order and to whom to ring. In Bitrix24 this is "Call processing scheme" for each number:
- Queue — call is distributed among managers in rotation.
- Simultaneously to all — all phones ring at once, first to pick up answers.
- IVR — voice menu with transfer to needed department.
Outgoing calls via trunk
By default, outgoing calls from Bitrix24 go through the platform's internal balance. To use your operator's rates, in settings you need to specify: "Outgoing via SIP trunk [trunk name]". Then the call goes through the connected trunk, and the operator charges it according to their rates.
Connecting a ready SIP trunk with credentials from the provider takes 1-2 hours including testing of incoming and outgoing calls.