3CX Softphone V5.8: Practical Improvements for Business Users

Small changes to a calling app can make a noticeable difference to a busy reception or sales team. Signing in, choosing the number used for a callback and transferring a caller are tasks people repeat throughout the day.

3CX announced the production release of Windows Softphone V5.8 on 6 October 2026. It introduces Google and Microsoft 365 sign-in, outbound-number selection and a configurable default for BLF transfers. The new features described in the announcement require the phone system to run V20 Update 10.

Easier sign-in for business users

After entering the 3CX server address, users can choose Google, Microsoft 365 or email sign-in. Google and Microsoft 365 authentication takes place through the browser before provisioning information returns to the app.

For a company using a central identity platform, this is a reason to review how staff join and access the phone system. Confirm the intended account works on a pilot device before preparing instructions for the wider team. Keep the instructions specific to your environment so users know which server address and account to use.

Choose an assigned outbound number

When an administrator enables the feature, users with multiple assigned numbers can choose a number through the “Call using” selector. The default route still follows the configured outbound rules. The permission is disabled by default.

This can be useful for someone working across departments, where returning a call using the appropriate business number helps the recipient recognise it. It is worth agreeing the intended use with team managers before enabling the option.

As a deployment check, call a controlled external test destination and confirm what number it receives. Do not assume that selecting a number in an app proves how it will appear through your particular SIP service. Also test what happens when that number is called back: the return journey should reach the intended team.

Make transfers more predictable

V5.8 allows a default blind or attended transfer method for BLF keys. A manual transfer choice on the keypad takes priority for that transfer. BLF keys provide shortcuts associated with extensions, making this setting relevant to users who transfer calls frequently.

An attended transfer lets a colleague speak to the receiving person before completing the handover. A blind transfer sends the call onwards without that preliminary conversation. The best choice depends on the team’s workflow: a reception desk handling sensitive enquiries may want a different habit from a team making routine internal handovers.

Train users with a short practice call. Ask them to try an available colleague, a busy colleague and an unanswered destination. The purpose is to confirm that both the application behaviour and the wider call flow match expectations.

Plan a small rollout before updating everyone

The official V5.8 release announcement links to the Microsoft Store download and advises removing an installed beta before using the production version. Check the existing app version and the PBX update level before starting.

• Pilot the release with users who represent your normal workflows.
• Check sign-in, audio devices, incoming calls and outbound calls.
• Test assigned numbers and callback destinations where used.
• Agree the BLF transfer default and give staff clear instructions.
• Record problems before expanding the rollout.

Get support for your 3CX apps and platform

I.T Communications provides UK 3CX support for administration, faults and planned upgrades. We can help assess the existing environment and coordinate app changes with the phone system’s configuration.

Ask about support for your 3CX upgrade, or call 03300 250 250.