I was wondering as part of my testing on my private O365 tenancy, how I could find out where in the world my mailbox was being hosted.  It is actually relatively simple to do – all you need to do is open PowerShell and get a connection to Exchange Online:

# CONNECT TO EXCHANGE ONLINE
$exchangeSession = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri "https://outl
ook.office365.com/powershell-liveid/" -Credential $credential -Authentication "Basic" -AllowRedirection
Import-PSSession $exchangeSession -DisableNameChecking -AllowClobber

# FIND SINGLE USER MAILBOX LOCATION
Get-Mailbox -Identity "first.last@contoso.com" | fl OriginatingServer, OrganizationId

# FIND ALL USERS MAILBOX LOCATION
Get-Mailbox -ResultSize Unlimited | fl OriginatingServer, OrganizationId

If you run the single user command, you should get some nice output like the below:

OriginatingServer : LNXP265A002DC01.GBRP265A002.PROD.OUTLOOK.COM
OrganizationId    : GBRP265A002.PROD.OUTLOOK.COM/Microsoft Exchange Hosted Organizations/contoso.onmicrosoft.com -
                    GBRP265A002.PROD.OUTLOOK.COM/ConfigurationUnits/contoso.onmicrosoft.com/Configuration

Here I can see that the OrganizationId (American spelling 😉 ) begins with GBR, which you can probably make a guess that it is hosted within Great Britain.  I don’t know if there is a list that you can go and lookup for the originating area codes etc, but I would be interested to see this list if anyone can provide a link and I will update my blog post!