Configure SMS/MMS in 3CX v20 with TELIN SIP Trunk | Step-by-Step Guide

Configure SMS/MMS in 3CX v20 with TELIN SIP Trunk | Step-by-Step Guide

Introduction

SMS and MMS are essential tools for modern business communication, enabling partners to extend customer engagement beyond voice. TELIN’s  SIP trunking service includes full support for SMS/MMS in 3CX Version 20, allowing you to manage calls, messages, and multimedia seamlessly under one roof.
This guide walks you through configuring SMS/MMS in 3CX with TELIN’s SIP trunk template, ensuring your business benefits from reliable delivery, correct caller ID handling, and TELIN’s Partner Success support.


Prerequisites

Before starting, make sure you have:

  • A TELIN One.Console account with SMS-enabled DID numbers.
  • 3CX Version 20 installed and accessible.
  • Administrative access to your 3CX Management Console.
Note: If your SIP trunk already has phone numbers assigned, ensure they are SMS/MMS capable. If you need to adjust numbers, refer to our article: [How to Add or Remove Phone Numbers in One.Console].

Step 1 – Access the 3CX Management Console

  1. Log in to your 3CX Management Console.
  2. Navigate to Admin > Advanced > Templates > Provider Templates.

Step 2 – Import TELIN’s Custom SIP Trunk Template

TELIN provides a custom SIP trunk template designed specifically to support both SMS and external forwarding.

  1. Select Import Provider.
  2. Upload the .xml file provided by TELIN (attached in this article)
  3. Once imported, TELIN will appear as a provider option in 3CX.

Step 3 – Configure the Trunk

  1. Navigate to SIP Trunks.
  2. Click Add SIP Trunk and select TELIN from the provider list.
  3. Enter your Registrar/Server details (copied from your existing trunk).
  4. Transfer your DID numbers and set your Default Outbound Caller ID under:
    Options > Caller ID Control > Default Outbound Caller ID.

Step 4 – Enable SMS/MMS

  1. Go to the TELIN SIP Trunk Settings.
  2. Locate the SMS Tab.
  3. Enable SMS/MMS and configure your account SID and token provided in One.Console.
  4. Save and apply changes.
Step 5 – Update Rules

  • Outbound Rules: Adjust so SMS and calls route through the new TELIN trunk.
  • Inbound Rules: Verify that SMS-capable numbers are linked correctly to extensions or queues.
  • Emergency Rules: Reconfirm settings under Admin > System > Emergency.

Step 5 – Update Rules

  1. Outbound Rules: Adjust so SMS and calls route through the new TELIN trunk.
  2. Update your inbound call routing.: Verify that SMS-capable numbers are linked correctly to extensions or queues.
  3. Emergency Rules: Reconfirm settings under Admin > System > Emergency.

Conclusion


By configuring SMS/MMS in 3CX (Version 20) with TELIN, you unlock more than just messaging — you provide clients with multi-channel communications backed by TELIN’s global Tier 1 network and full Partner Success Program support.
With TELIN, partners gain:
  1. Reliable SIP trunking (One.Voice) with SMS/MMS support.
  2. Centralized management via One.Console.
  3. 24/7/365 technical support from certified engineers.

TELIN ensures your unified communications platform remains secure, scalable, and stress-free.

    • Related Articles

    • One.TelcoBill: Your White-Label Telecom Billing Solution

      Welcome to the One.TelcoBill guide! This article will provide you with all the essential information you need to get started with One.TelcoBill, a comprehensive white-label telecom billing solution designed for MSPs, resellers, and telecom service ...