3CX features and what they mean

3CX Features and what they mean

In order to be able to advise your clients on whether 3CX is right for their business, you are going to need to know what it can do. In another blog post we talked about 3CX’s limitations, check those out here.

Let’s dive into the list of 3CX features and what they mean.

If you’re feeling overwhelmed by the sheer number of 3CX features (to which 3CX keeps adding more features to every year) and want to talk to a “3CXpert”, excuse the pun, the Lightwire team is always more than happy to take your call or email

List of 3CX Features

Here is a comprehensive list of 3CX features. Click on any of the features below to find out what they mean in real terms. 

Please note that access to these features will be determined by license type.

3CX Core PBX Features


This effectively means “users”. Each extension represents a user or end device (such as a meeting room phone). 3CX offers unlimited extensions, making it the market leader in cost-effective scalability.

Import / Export Extensions via CSV

Back up extension configurations directly. Also, configure large numbers of extensions in a CSV editor and import them at once.

SIP Trunks / Gateways Support

Allows for multiple trunks, which can be used to split out call charges to different departments and/or allow for cost-effective local call break out (e.g. NZ SIP trunk for calls from your client’s NZ team and an Australian SIP trunk for their AU based team).

Call Routing by DDI & CID

Set rules for each inbound number to route calls appropriately, which can also switch based on office hours. Also allows you to specify a rule for caller numbers, which can be wildcarded which means you can implement specific rules based on inbound prefix. (for example, any caller number that starts with a certain area code goes to a certain team). This can be used to have high value clients route to their account manager directly for example, or send nuisance callers to voicemail.

Extensive Codec Support

There are several codecs available that encode and decode audio in different ways, which can affect the quality of a call, as well as bandwidth use. 3CX can “transcode” these calls if necessary to make sure that call audio comes to a device in a format it understands. In general however, only one codec (PCMA) is used by the Public Switched Telephone Network (PSTN), making it simpler to just use that codec for all calls.

Voicemail to Email

Notify your users of a voicemail being left for them by email, and even attach the message itself so that it can be listened to remotely via a mobile device.

Calling Line Identification Presentation (CLIP)

The technical name for “Caller ID”.

Call Transfers (Blind & Attendant)

Users can transfer calls to other extensions or external numbers. This can be done immediately and directly (blind) or by placing the other party on hold and speaking to the transferee before completing the transfer (attendant).

Calling Line Identification Restriction (CLIR)

Using a special dial code 3CX can withhold your outbound calling number, so that the recipient simply sees “Unknown” or “Private Number”. This meets legal requirements as set by regulatory bodies in the Australian and New Zealand markets. This cannot however be set on a permanent basis and meet the requirements.

Call Forward on Busy (CFB)

Set a rule for each extension to forward a call to a specific place if it’s busy on a call.

Call Forward on No Answer (CFU)

Set a rule for each extension to forward a call to a specific place if it doesn’t answer a call within a configured timeframe.

Hold (CW) incl. Custom Music on Hold

Place callers on hold. You’re able to configure your own music that will play while the caller is on hold, however, please note that this is considered broadcasting and a license would be required for any copywritten content.

Intercom / Paging / PA Announcements

The 3CX desktop apps, as well as certain hardware, can be configured to act as paging devices. A user can dial a code then the extension or group number, and then speak openly via the speakers on these devices to make announcements. Specialised hardware is also available to allow for public announcements. 

Call Parking / Pickup

Place a call on hold, which allows another user to pick up the call and take over.

Busy Lamp Field (BLF)

Specialised buttons on phone handsets as well as the 3CX desktop apps show a coloured light detailing whether another user is available, already on a call, or offline. This doesn’t show whether they have set their extension to away however. 

Real Time System Status

The management console has a simple dashboard that shows clearly how many calls are active and how many extensions are registered, as well as CPU, memory, and disc usage.

Easy Backup and Restore (incl. Scheduled Backup)

Take and download backups as required, as well as being able to easily restore the configuration from a backup stored on the instance. Lightwire configures all 3CX PBXs that it manages to be backed up nightly. These backups are also copied to another storage and retained for change control.

VMware / Hyper-V / KVM Compatibility

3CX is tested and supported to run as a Virtual Machine on these hypervisor platforms:

  • VMware vSphere Hypervisor (ESXi) 6.5u1 and above.
  • Microsoft HyperV (6.2) and above capable of running Win 10 or Server 2016 and above.
  • KVM 2.8 and above.
  • Citrix XenServer 7.0 and above.

Amazon, Google Cloud, Microsoft Azure

3CX is tested and supported on multiple cloud hosting platforms. Lightwire hosts all of its managed PBXs in Amazon Web Services.

This blog post has detail on 3CX hosting requirements. 

3CX SBC Connectivity

3CX generally works very well for remote deployments, with the PBX running in the cloud or off-site. In a small number of cases remote users may experience issues due to firewall configurations, the use of hardware that can’t be used remotely, or required features that require local access (such as Hotdesking).

3CX provides Session Border Controller (SBC) software that can be configured in a Windows or Debian host on the local network, which works as a proxy, talking to local devices directly and communicating with the remote PBX via its tunnel protocol.


Every extension has a voicemail inbox, which can be disabled if needed. There is no limit on the number of voicemails that can be left in a single mailbox, however messages do require around one megabyte per minute of storage space, so physical storage could become a limitation. There is a maximum duration of 120 seconds, however, this can be changed.

Messages can be retrieved via a call to a dedicated extension or by email. The email option allows for a choice of a simple notification, or the message attached as a WAV file, with the attachment giving the choice of automatically removing from the 3CX inbox
to save storage.

3CX’s handling of “group mailboxes” is limited, with it only allowing for messages to be emailed to the users defined in the “Ring Group” or “Queue” used and no provision for a custom outgoing message. The workaround is to set up an extension and upload the required outgoing message and email the messages to a group mailbox or distribution list.

The total storage space used can be given a maximum quota by the system administrator.

Voicemail Transcription

With a separate Google Cloud account, 3CX can use Google’s Speech to Text API to transcribe voicemail messages, and include the text in notification emails as well as in the 3CX Web Client.

Google’s API allows for a maximum of one minute of transcription, so messages longer than this may not be transcribed in full.

Custom FQDN

Configure your PBX to be accessible at a URL of your choice, rather than use 3CX’s domain names. Lightwire makes use of this to offer PBXs at lightwirevoice.com and siphost.co

Custom SMTP Server

Use your own email server for outbound emails

3CX Office Productivity Features

Auto Attendant / Digital Receptionist

Create your own menus to allow callers to get routed to the right staff member. By default this also allows a caller to dial the extension they wish to speak to directly.

Ring Extension & Mobile Simultaneously

When a call is made to an extension 3CX can simultaneously forward it to the user’s mobile number so that it can be answered on either. This can be set on a per-extension basis and can also be set for specific user states (so the user can turn it off and on).

Integrated Fax Server (Central and per User)

Faxes can be sent to 3CX, which can email the messages as a PDF attachment. This can be sent to a default email address or the email address associated with a specific extension. There are some caveats, however:

  • 1. It is preferable if the SIP Trunk supplier is able to trunk T.38 (Fax over IP protocol). There is beta functionality that supports failover to an audio codec, however this has been found to be somewhat unreliable.
  • 2. 3CX doesn’t include an outgoing email to fax server, so another solution is required to send faxes.

Supported SIP Phones Integration

SIP Phone manufacturers have worked with 3CX to make their handsets completely compatible. A list of these devices is available here.

Manage IP Phones Network Wide

When 3CX is deployed locally or using an SBC, handsets on the network can be found and configured directly from the 3CX management console.

Automatic Plug & Play Phone Provisioning

As above

3CX Apps: Windows and Web Client, iOS, Android

3CX offers applications that are native to iOS and Android and are available in the relevant app store. A web client is available for access anywhere, which can also be installed directly into the Chrome and Edge browsers on all operating systems (Progressive Web App or PWA), and there are Windows and MacOS desktop applications.

Directory (Company & Private Phonebook)

All users have access to a private contact list/phonebook, and a company-wide contact list is available and able to be managed by specific users.

Sync with Office 365 (Users’ Phonebook)

3CX can integrate with Microsoft 365, and automatically synchronise users’ phone books with their Outlook address book. It is also possible to synchronise the user’s calendar, to change the extension state depending on meetings and appointments.

Call Query against DB & CRM

3CX can integrate with many CRM platforms to retrieve caller details and set up call journaling.

Hotel PBX Features incl. Fidelio Certified and Mitel Compatible

3CX integrates with multiple hotel systems, and offers features like Wake-Up Calls

Web Conferencing

3CX has a built-in video conferencing solution that can be used for meetings with internal and external parties. Web conferences can be set up on an ad-hoc basis or scheduled in advance with integration with many calendar products.

3CX Call Centre Features

Call Logging

All calls are logged and available for review from the management console.


You can provide users with a web URL to chat with a user or even a calling queue directly and allow them to call from their web browser. This requires the use of Firefox, Chrome, or Edge browsers.


You can provide a web URL to set up ad-hoc video meetings with you.

Website Live Chat and Talk

Live chat can be integrated into your website, allowing users to contact your customer service team directly via chat and voice calls, right in the browser.

CRM Integration

3CX can integrate with many CRM solutions, retrieving details about callers from your records, and even allowing call journaling and ticket creation.

Sync with Office 365 (Azure AD)

3CX can integrate with Microsoft Office 365 via an Azure Active Directory application, and perform functions such as automatically creating new extensions when a user is created in Office, syncing user and company phone books, and automatically switching extension state with calendar events.

Call Queuing

If your team are already on calls when a new call comes in, that call can be held until one of your team is available to accept it.

Supervisor Agent Status Override

Certain users can be set as “Queue Managers,” who can log agents in and out directly (if they forget to log out before going on break for example)

SLA Alerting

Automatically alert your queue managers by email when a call has exceeded a preset hold time.


Easily see how many people are waiting for a call to be answered or already speaking to a caller, and transfer calls between people as necessary.


A simple dashboard to show how many callers are waiting for an agent, and other details such as average wait time, call time, and number of calls taken and missed.


When configured, callers can select to have 3CX call them back when it is their turn to speak to an agent. A call is sent to the agent and rings out.

Call & Queue Reporting

Multiple options for reports detailing things like wait times, talk time, number of calls abandoned, and so on.

Check out this blog to see what 3CX reports look like.

Barge In / Listen In / Whisper

Rights can be given to specific users to allow them to “Barge In” to an active call (create a three-way call), “Listen In” (hear both sides of the conversation with themselves muted), or “Whisper” (speak to one party on the call, without the other party hearing). This can be useful for training and call quality purposes.

See Group Recordings

Users can be given rights to see the recordings for other people in their extension group directly in the webclient, which can be useful for managers performing call quality checks, or training purposes.

3CX Enterprise Features

Call Flow Designer

The Call Flow Designer is a Windows application that allows you to build more complicated IVRs and call routing logic than 3CX is capable out of the box. This allows, for example, calls to be routed via more complex time of day rules, transfers to different teams based on the caller’s phone number, caller verification via PIN number, and much more.

The Call Flow Designer application is effectively a set of components that are built in a flow-chart configuration (with certain components able to have more complex C# code written into them), and when built this can be uploaded into 3CX and calls routed to them directly

Hot Desking

Supported desk phones can be configured to allow users to dial a short code, then their extension number and voicemail PIN, to set them up for their own use. This can take around five minutes to set up, as it requires the phone to retrieve the configuration and reboot itself. This function requires that the PBX be hosted on the local network, or using a local SBC (it can’t be used for remote deployments via STUN).

Scheduled Restore

This allows for the PBX to restore its configuration from a backup on a set schedule. This is typically used for the “failover” functionality, with the second backup instance restoring its configuration from the live system periodically.

Connect Remote Offices (Bridges)

3CX systems can be “bridged” together, so that calls between the two can be routed directly between them, rather than having to go externally. The typical use case for this would be when there are different branches of a business, each with their own 3CX system.

Bridging will allow each branch to call extensions at the other branch directly (using a prefix) without having to dial their public number. Extension presence can be published across the bridge as well, so staff at one branch can see easily from the webclient whether staff at the other are logged in and ready for calls

Call Recording Restrictions (Start/Stop)

Users can be given rights to start and stop call recordings when needed, directly from the web client or desktop app. This could be useful if only certain conversations need to be recorded for compliance reasons.

Skill based Routing

Agents in your calling queues can be given a ranking from 1 to 5. With a Skills Based routing strategy, agents with a higher ranking will only be polled if there are no agents available with a lower ranking; ie, you can have your Tier 2 staff receive calls only if all Tier 1 staff are busy on calls.

Inbuilt Failover

When using an Enterprise license, and a 3CX provided FQDN, you can run two separate instances of 3CX in an Active – Standby configuration. These could be two separate machines at diverse locations, or an on-premise machine and cloud instance. If the Active instance becomes unreachable for any reason, 3CX can failover the domain name to the Standby instance within 60 seconds (TTL).

This does require that all extensions be provisioned against the domain name, and you would require backups on the Active instance to be saved to a location reachable from the Standby, ie to a cloud storage bucket. If using custom FQDNs (ie Lightwire’s hosted instances) the Domain provider would need to handle failing over; 3CX cannot do this automatically.

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