What phone number or SIP URI could be assigned to Teams users/desk phones?

New Contributor

Hello all,


Just try to set up the 1st MS Teams desk phone(Yealink) in our environment.     


We have O365 E3 + Phone system license.  No phone number port over.   Deployment model: Direct Routing.  My understanding is Microsoft won't assign any "Microsoft" phone number to the user/phone.


Questions :

. What "phone number" or SIP URI could be assigned to Teams user/ Teams desk phone? 

. When outside caller try to make a call to this Teams phone through analog phone,  how this caller could dial?   


Any information or help will be appreciated. 


Best regards,



8 Replies



You can assign a number from Direct Routing or Calling Plans, but since you have Direct Routing you should take a direct routing number and assign to the user account.


The number is not assigned to the deskphone, it is assigned to the user account that signs in to the phone.


When a outside caller makes a call to the user that is signed in to the deskphone the call will go from PSTN to Direct Routing SBC (your own or hosted) to Microsoft and then to the Teams user (signed in to Teams client in computer or/and deskphone).

@Linus Cansby 


Thanks for your reply, Linus.

Can you please kindly advise what the "direct routing number" could be?  Available DIDs?


I don't have Calling Plans license.

What I have :   availabe DIDs from local Telco service provider;

internal extension phone number;  on-premises IP-PBX; on-premises SBC(testing now).


Just a thought:

Maybe I could assign any one of available DIDs as the "direct routing number"?
And program the phone number or some routing rules on the on-premises SBC?

Then the inbound calls could go through (PSTN ->on-premises voice gateway->) SBC->Teams->Teams desk phone. 



Best regards,




best response confirmed by Howard Zhou (New Contributor)

@Howard Zhou The DID that you get from your local Telco service provider is the Direct Routing numbers that you can assign to an user.

@Howard Zhou Hi Howard, you should purchase DID numbers from your SIP trunk provider. I presume your SIP trunk provider is also hosting the SBC?


You will need to pair the SBC to your office 365 tenant using powershell. And you will also be able to assign DID numbers to users via powershell.


Once this is done any users who have the phone system add-on will be able to make and receive calls using Teams.





I see Linus.
Thanks for your response.

Since we assign DID as Direct Routing number, how does SBC route the call to Teams users/phone from SBC ? I mean when user dials the "Direct Routing number".

Should something i.e. call routing rules are required to set up on the on-premises SBC?

Hi Howard,

You need to pair the SBC to your 365 tenant and allocate DID numbers to the users via powershell.

There's approx. 10 lines of powershell commands.

If you need any more help with this please let me know.

Hi @Howard Zhou ,

have you been involved in the setup of the SBC? Is the SBC really implemented for Direct Routing? 

Yes, there has to be routing setup on on-premise SBC for numbers that are assigned to Teams users. 

And not only there... if there is any on-premise PBX between gateway and SBC you have to setup even routing rules to route numbers for Teams users to the SBC from local gateway.

If your SBC serves as gateway too and basically all calls are routed to SBC and then to Teams then you are missing only part when Teams user logged in Yealink phone has to be configured as EnterpriseVoice enabled, has to have OnPremLineURI set and if you have your Phone System in cloud provisioned already for Direct Routing then also some OnlineVoiceRouting Policy would be necessary for such user in order to make outgoing calls. 



Thanks @DaveChomi

Yes - SBC is implemented for Direct Routing. It doesn't serve as gateway, Just routes the calls to/from Teams users.

We support Ukraine and condemn war. Push Russian government to act against war. Be brave, vocal and show your support to Ukraine. Follow the latest news HERE