Office 365 Enterprise E5 (without Audio Conferencing)

If you have already purchased the Office 365 Enterprise E5 (without Audio Conferencing) plan, here are the Skype for Business add-on licenses you need to buy to get more features.

To add this feature
Here's what you need to buy
Audio Conferencing
To get this add-on, do the following:

1. If you have already bought an E5 plan but the Audio Conferencing feature isn't available in your country or region, you will need to use a third-party audio conferencing provider. Find a third-party audio conferencing provider at Microsoft PinPoint.

Check this article to see if Audio Conferencing is available in your country or region: Country and region availability for Audio Conferencing and Calling Plans

2. If it is available, use the Switch plans button to move to the Office 365 Enterprise E5 that includes it. You'll get more features, too!
Phone System is included!
Calling Plans: buy a Calling Plan from Office 365.
Or, use the telephone service from your existing provider.
Cloud Voicemail is included!
You don't need anything else.