3CX Phone System 15.5 review: Making all the right calls

3CX’s affordable Phone System is the IP PBX host with the most and a great choice for SMEs

IT Pro Verdict

We were extremely impressed with how easy it was to deploy the 3CX Phone System software and the range of communications features on offer. SMEs that want to host their own IP PBX are looking at the best solution money can buy.


  • +

    Super-easy setup and provisioning; Great management tools; Excellent call handling options; Highly affordable


  • -

    Nothing to speak of

SMEs that want to host their own IP PBX will love 3CX's Phone System, as it offers every feature they could possibly need. Furthermore, pricing is based on the number of simultaneous calls and not physical extensions, making it even easier to choose the right license.

3CX also offers a free 16SC version which supports 16 simultaneous calls and includes maintenance for the first year. If you don't renew the contract after this period, it automatically drops to the 4SC version which includes perpetual updates.

You can host Phone System on a Windows or Linux server, run it on a mini PC, virtualize it on Hyper-V, VMware or KVM hosts or cloud host it with providers such as Amazon Lightsail, Google Cloud and Microsoft Azure. If you decide to go from on-premises to the cloud, the new PBX Express tool migrates your IP PBX without losing your settings.

For testing, we used an HPE ProLiant DL20 Gen9 rack server equipped with a 3.4GHz Xeon E3-1230 v5 CPU and 16GB of DDR4 - powerful enough to handle 256 simultaneous calls. Software installation is swift and the setup wizard had us up and running in 30 minutes.

We needed to open up SIP and RTP ports on our firewall using port forwarding rules, but 3CX provides detailed online tutorials. On completion, a firewall checker tested all required ports and gave us a green light to continue.

3CX requires an external FQDN (fully qualified domain name) and SSL certificate to ensure remote users can connect securely to the IP PBX. It can provide these services for you and they will still continue to function even if you're running the free 4SC version.

Just create an extension number for each user; importing them from Active Directory adds details such as email addresses and mobile numbers. 3CX also provides SMTP services and users receive an email with extension details, voice mail access PIN and a download link for the 3CX Windows softphone along with a registration file.

IP phone provisioning is a walk in the park: our Yealink T23G phones appeared in the console as soon as they came online. After assigning them to each user, they were set up automatically and even had their firmware updated to the latest version.

3CX offers a stunning range of call handling features and its smart console provides easy access to them. Inbound rules allowed us to assign our SIP trunk phone number aliases to selected extensions and route them to voicemail or an external number outside of office hours.

Caller ID inbound rules route calls from specific numbers to selected extensions while call queues and ring groups ensure calls are always answered. Outbound rules control all aspects of outgoing calls and for backup, you can assign up to 5 SIP trunks.

A digital receptionist ensures callers go to the correct person by presenting them with custom messages and menu options. Each user can have their calls recorded to the Phone System host as WAV files while hot-desking in the Pro and Enterprise versions allows selected extensions to be shared by multiple users.

Free softphones for Windows, Mac, iOS and Android devices are provided and we registered our iPad by scanning the QR code in our personal web portal. The portal also provided quick access for running web meetings or conferences and accessing call features, chats, contacts and voice mail.

A great combination of call handling features and deployment options makes 3CX's Phone System the perfect choice for SMEs that want to host their own IP PBX. It's easy to install and manage and simply won't be beaten for value.


We were extremely impressed with how easy it was to deploy the 3CX Phone System software and the range of communications features on offer. SMEs that want to host their own IP PBX are looking at the best solution money can buy.

Windows 10, Server 2012 upwards

Linux Debian 8 upwards

Dave Mitchell

Dave is an IT consultant and freelance journalist specialising in hands-on reviews of computer networking products covering all market sectors from small businesses to enterprises. Founder of Binary Testing Ltd – the UK’s premier independent network testing laboratory - Dave has over 45 years of experience in the IT industry.

Dave has produced many thousands of in-depth business networking product reviews from his lab which have been reproduced globally. Writing for ITPro and its sister title, PC Pro, he covers all areas of business IT infrastructure, including servers, storage, network security, data protection, cloud, infrastructure and services.