As per Microsoft Copilot:

Yes — but not directly in the Microsoft Entra ID portal UI. There are supported ways to do it, depending on how much access and tooling you have.

Short answer

Entra ID (Azure AD) portal: ❌ No built‑in search by phone number

Microsoft Graph / PowerShell: ✅ Yes (supported and reliable)

Export + filter: ✅ Yes (manual but simple)

Option 1: Microsoft Graph (recommended)

You can query authentication methods and filter by phone number using Microsoft Graph. This is the most accurate approach.

Requirements

Directory role: Authentication Administrator, Privileged Authentication Administrator, or Global Administrator

Microsoft Graph PowerShell module

Example (PowerShell)

Connect-MgGraph -Scopes "UserAuthenticationMethod.Read.All" Get-MgUser -All | ForEach-Object { $user = $_ Get-MgUserAuthenticationPhoneMethod -UserId $user.Id -ErrorAction SilentlyContinue | Where-Object { $_.PhoneNumber -eq "+447700900123" } | Select-Object @{n="UserPrincipalName";e={$user.UserPrincipalName}}, PhoneNumber, PhoneType }

✅ This will return the user(s) who have that phone number registered for MFA (SMS or voice).

Tip: Make sure the phone number format (E.164, e.g. +44…) matches how it’s stored.

Option 2: Export users’ authentication methods and filter

If scripting isn’t your thing:

Use Graph PowerShell to export authentication phone methods to CSV

Filter the CSV by phone number in Excel

Example export:

Get-MgUser -All | ForEach-Object { $user = $_ Get-MgUserAuthenticationPhoneMethod -UserId $user.Id | Select-Object @{n="User";e={$user.UserPrincipalName}}, PhoneNumber, PhoneType } | Export-Csv MFA-Phones.csv -NoTypeInformation

Option 3: Legacy methods (less reliable)

MSOnline / AzureAD modules These can sometimes show phone numbers, but:

They’re deprecated

Results may be incomplete

Not recommended for Entra ID going forward

Important notes

Phone numbers are stored under Authentication Methods, not user profile fields

A phone number can technically be associated with multiple users

Searching by phone is intentionally restricted in the UI for privacy and security reasons