How to Migrate Tenant to Tenant Telephone Numbers in Office 365?

This article will outline the steps for how to move numbers from tenant to tenant in Office 365. The first task we need to do is to have the information required.

How to Migrate Tenant to Tenant Telephone Numbers in Office 365?

Content Summary

Source Tenant domain name
Source tenant unique identifier
Destination Tenant name and a unique identifier
Numbers
Addresses
Request date and time
Template

Source Tenant domain name

Step 1: Log in to Office 365 Admin Center as an administrator.

Step 2: Click on Domains under Setup. (or this direct link).

Step 3: Find the domain that ends with .onmicrosoft.com which is your Office 365 tenant name.

Source tenant unique identifier

Tenant unique identifier also known as globally unique identifier or GUID of your tenant which can be found in the Tenant ID box on the Properties page.

Step 4: Go to Properties page.

Step 5: Locate Tenant unique identifier in the Tenant ID box.

Locate Tenant unique identifier in the Tenant ID box.

Destination Tenant name and a unique identifier

Step 6: You also need this same information for the destination tenant, follow the above mentioned steps to get the Office 365 destination tenant domain name, the Office 365 destination tenant unique identifier.

Numbers

Step 7: The Number(s) which are to be ported from source to destination tenant. These need to be broken down as a user number or a service number.

  • User numbers are applied to a user.
  • Service numbers are applied to Auto attendants, call queues or virtual numbers which need to follow a particular function but are not attributed to a physical user.

Addresses

The addresses on the Office 365 destination tenant for user numbers will need to be supplied. Follow below steps to find out the used addresses.

Step 8: Login to Teams Admin Centre.

Step 9: Go to Locations > Emergency Addresses. Copy this list of output for all the addresses currently in use in order to be added back into the Teams Admin Center from the source to the destination Emergency addresses.

Copy this list of output for all the addresses currently in use in order to be added back into the Teams Admin Center from the source to the destination Emergency addresses.

Step 10: To create the emergency locations, click on New and input the information.

Step 11: Press Save, Microsoft will start to validate the address. This validation will need to be completed before the numbers can be assigned to the tenant.

Press Save, Microsoft will start to validate the address. This validation will need to be completed before the numbers can be assigned to the tenant.

Request date and time

Step 12: Send all the compiled information to Microsoft for further review and validation.

Step 13: Microsoft will reply you that the request is successful or if further review is required.

Step 14: Microsoft will start the porting process on Monday-Friday (no national or bank holidays) and it’s 8-5pm UK time for Europe and the same is applicable for the United States.

Template

Office 365 source tenant domain name
Office 365 source tenant unique identifier
Office 365 destination tenant domain name
Office 365 destination tenant unique identifier
Number(s) to be ported from source to destination tenant
As User
As Service
Address on the destination tenant for user numbers
Requested date and time range of port request executionAvailable times:
Monday – Friday
8am – 5pm