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policy-all-users-mfa-strength.md

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title Require MFA for all users with Conditional Access
description Create a custom Conditional Access policy to require all users do multifactor authentication.
ms.topic how-to
ms.date 04/01/2025
ms.reviewer lhuangnorth

Require multifactor authentication for all users

As Alex Weinert, the Director of Identity Security at Microsoft, mentions in his blog post Your Pa$$word doesn't matter:

Your password doesn't matter, but MFA does! Based on our studies, your account is more than 99.9% less likely to be compromised if you use MFA.

Authentication strength

The guidance in this article helps your organization create an MFA policy for your environment using authentication strengths. Microsoft Entra ID provides three built-in authentication strengths:

  • Multifactor authentication strength (less restrictive) recommended in this article
  • Passwordless MFA strength
  • Phishing-resistant MFA strength (most restrictive)

You can use one of the built-in strengths or create a custom authentication strength based on the authentication methods you want to require.

For external user scenarios, the MFA authentication methods that a resource tenant can accept vary depending on whether the user is completing MFA in their home tenant or in the resource tenant. For more information, see Authentication strength for external users.

User exclusions

[!INCLUDE active-directory-policy-exclusions]

[!INCLUDE active-directory-policy-deploy-template]

Create a Conditional Access policy

The following steps help create a Conditional Access policy to require all users do multifactor authentication, using the authentication strength policy, without any app exclusions.

Warning

External authentication methods are currently incompatible with authentication strength. You should use the Require multifactor authentication grant control.

  1. Sign in to the Microsoft Entra admin center as at least a Conditional Access Administrator.

  2. Browse to Entra ID > Conditional Access > Policies.

  3. Select New policy.

  4. Give your policy a name. We recommend that organizations create a meaningful standard for the names of their policies.

  5. Under Assignments, select Users or workload identities.

    1. Under Include, select All users
    2. Under Exclude:
      1. Select Users and groups
        1. Choose your organization's emergency access or break-glass accounts.
        2. If you use hybrid identity solutions like Microsoft Entra Connect or Microsoft Entra Connect Cloud Sync, select Directory roles, then select Directory Synchronization Accounts
      2. You might choose to exclude your guest users if you're targeting them with a guest user specific policy.

  6. Under Target resources > Resources (formerly cloud apps) > Include, select All resources (formerly 'All cloud apps').

    [!TIP] Microsoft recommends all organizations create a baseline Conditional Access policy that targets: All users, all resources without any app exclusions, and requires multifactor authentication.

  7. Under Access controls > Grant, select Grant access.

    1. Select Require authentication strength, then select the built-in Multifactor authentication strength from the list.
    2. Select Select.

  8. Confirm your settings and set Enable policy to Report-only.

  9. Select Create to create to enable your policy.

[!INCLUDE conditional-access-report-only-mode]

Named locations

Organizations might choose to incorporate known network locations known as Named locations in their Conditional Access policies. These named locations might include trusted IP networks like those for a main office location. For more information about configuring named locations, see the article What is the location condition in Microsoft Entra Conditional Access?

In the previous example policy, an organization might choose to not require multifactor authentication if accessing a cloud app from their corporate network. In this case they could add the following configuration to the policy:

  1. Under Assignments, select Network.
    1. Configure Yes.
    2. Include Any network or location.
    3. Exclude All trusted networks and locations.
  2. Save your policy changes.

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