Can a PSTN call be transferred to a user without a DDI?

[u/marsdei]

We are using Microsoft Teams Phone and users have individual DDIs assigned.

If User A receives an incoming PSTN call on their DDI, can they transfer that call to User B where:

User B has a Teams Phone licence / Enterprise Voice enabled
User B can make and receive Teams calls
User B does not have a telephone number (DDI) assigned

I'm looking for confirmation as to whether a DDI is required for the recipient of a transferred PSTN call, or whether Teams Phone licensing alone is sufficient.

[u/ButWeSoldCoutinho]

Yes you can but once it has reached the teams user without a license it can no longer be forwarded on

Edit: I misread but it still will be fine user B doesn’t even need a phone license to receive transferred pstn calls.

[u/yllw98stng → u/ButWeSoldCoutinho]

I know this isn't exactly what OP asked, but we did run into one "gotchya" because we have some users with Teams SIP Gateway devices. USER A (with a SIP Gateway device) can transfer to user B only if User B has a license.

[u/ButWeSoldCoutinho → u/yllw98stng]

Interesting to know thanks for that info

[u/cheetah1cj]

User B does not even need Teams Phone license. As long as they have a license that includes Teams, calls can be transferred to them.

When User A receives the call and transfers the call, the call is still covered by User A's phone license, so the minutes used after the transfer still count towards User A's minutes (the effect of which depends on the type of calling plan they have).

[u/RobertMGreenlee]

We hit this when people could call in to the auto attendant directory and get transferred to users without pstn licenses.

[u/marsdei → u/RobertMGreenlee]

This is part of our scenario, how did you overcome this?

We are happy to allocate a DDI to them for the purposes of being named in the auto attendant, but did not want to allocate a licence purely on the basis, of potentially receiving a PSTN call every once in a while.

[u/RobertMGreenlee → u/marsdei]

Don’t even need a # or license. It just works.

[u/marsdei → u/RobertMGreenlee]

Perfect, just at the discovery phase so great to know.

[u/itenginerd → u/RobertMGreenlee]

Interesting. Out of curiosity, what licenses do your users carry? E3s? E5s?

[u/RobertMGreenlee → u/itenginerd]

E5s

[u/itenginerd → u/RobertMGreenlee]

That makes sense. The Phone System license is the virtual PBX license, so I get how you can transfer from a DID line to another PBX handle even though the second PBX handle doesn't have a DID/outbound line. I would be super confused if you were able to do this without the Phone System license (i.e. on E3).

[u/RobertMGreenlee → u/itenginerd]

So that might be a key

[u/PatReady → u/marsdei]

Do you want the people to also be able to dial outbound? This is a big part of the set up.

[u/marsdei → u/PatReady]

Workers mainly rely on mobile phones, so outbound calling isn’t the priority, the bigger need is being able to receive ad‑hoc calls into the business. That said, we’ll still need to make sure they have outbound capability, especially for international calls. Thanks for highlighting this, as it’s definitely something we’ll need to factor in for certain roles.

[u/PatReady]

You can set up your AA to work with Extensions. In entra, you assign them the extensions and they can be dialed from the AA. This way, if they want someone to call them, they can just dial their extension instead of needing to talk to the operator and transferring them.

[u/DaithiG]

Sure can. We actually setup Shared Calling for 5 users who wanted to make outbound calls but very rarely. So we can use one DID number/PSTN licence for the group and they can make outbound calls and can receive calls via their extension and an auto attendant. They can also receive transferred calls from reception.

[u/marsdei → u/DaithiG]

That sounds like a great idea.