One Microsoft account covers Outlook/Hotmail mail, Xbox, OneDrive, Teams and Office — and at signup Microsoft regularly demands SMS confirmation, especially when registering from a VPN, a datacenter IP, or right after another account. A virtual number from Get-SMS passes this check and keeps your personal number out of the loop.
Microsoft's check is one of the fussier ones about reuse: a number that already confirmed a couple of accounts returns «This phone number has been used too many times». That's a property of the specific number, not the service — cancel it free of charge and take the next one, preferably from a different country pool. Canada, Morocco, Brazil, Hong Kong, and United Kingdom numbers all pass well.
Don't leave the one-time number as the only recovery method. Once the account exists, add a recovery email and, ideally, the Microsoft Authenticator app — Microsoft then stops relying on SMS for sign-ins. This matters because Microsoft is persistent about «unusual sign-in activity» challenges: if SMS remains the only second factor, you'll want a number that still works. For accounts that will hold subscriptions (Microsoft 365, Xbox Game Pass) or become work Teams identities, a 30-day rental during the setup period is the comfortable option.
Gamers take note: the same check covers Xbox Live. A Microsoft account verified once with a virtual number signs into the console, Game Pass and cloud gaming without any further SMS — the phone requirement is account-level, not device-level.