Do I have to use Microsoft Authenticator for my work account?

Not if your organization allows other apps. The setup screens push Microsoft Authenticator, but “I want to use a different authenticator app” accepts any app that generates standard six-digit codes, and the Authenticator extension reads the QR code straight off the Security info page. If your organization requires push notifications with number matching, those exist only in Microsoft Authenticator.

Why is there no “I want to use a different authenticator app” option?

Your organization’s administrator has not allowed third-party authenticator apps (Microsoft calls them software OATH tokens) for your account, or limits you to certain methods. Only the administrator can change that — ask your IT help desk which methods you may use.

What if I lose access to my authenticator?

Sign in with another method you added on the Security info page, delete the old authenticator there and add the new one. If you have no other method, your IT help desk can reset your sign-in methods so you can register again. With the extension, restoring one of its automatic backups on a new computer keeps the same codes working.

Is this the same as my personal Microsoft account?

No. A work or school account is managed by your organization at mysignins.microsoft.com; a personal Microsoft account — Outlook.com, Hotmail, Xbox, a personal OneDrive — is managed by you at account.microsoft.com. Each has its own authenticator setup, and the extension can hold both as separate entries.

Microsoft 365 Authenticator App — Set Up 2FA for a Work or School Account

A work or school account signs you in to Outlook, Teams, OneDrive and SharePoint for your organization — mail, chats, shared files, often the other business apps connected to it as well. One stolen password would open all of it, which is why organizations require a second step. If you would rather not put a work app on your personal phone, an authenticator in the browser on your work computer can supply the codes.

Add an authenticator app to your Microsoft 365 account

This guide is for the account your employer or school gives you (Microsoft Entra ID, formerly Azure AD). A personal Microsoft account — Outlook.com, Hotmail, Xbox — is set up at account.microsoft.com instead and has its own guide. Your organization’s administrator decides which methods you see: if “I want to use a different authenticator app” is missing, third-party authenticator apps are not allowed for your account, and Microsoft Authenticator’s push approvals only work in Microsoft Authenticator. If your organization signs you in through another system (Okta, Duo), the second step belongs to that system.

Sign in to the Security info page of your work or school account at mysignins.microsoft.com/security-info on your computer. If you are asked for “More information required” right after signing in, select “Next” — the “Keep your account secure” wizard offers the same choice as step 4.
Select “Add sign-in method”.
Choose “Microsoft Authenticator” and select “Add”. Some organizations’ pages list it as “Authenticator app”.
Microsoft suggests downloading its own app. Instead, select “I want to use a different authenticator app”, then “Next”.
When Microsoft shows a QR code, leave that page open and add it to the extension as described below — or select “Can't scan image?” to see a key for manual entry. Then select “Next” and enter the six-digit code from the extension.

Microsoft 365’s own instructions

Add Microsoft 365 to Authenticator

Install 2FA Authenticator from the Chrome Web Store and pin it to the toolbar, so its icon is one click away.
Leave the Microsoft 365 page with the QR code open. Click the Authenticator icon, then “Add Account” → “QR Code” → “Scan QR from screen”.
The account appears in the list with a six-digit code that changes every 30 seconds. Rename it if you like — the name is only for you.
Go back to Microsoft 365 and type the current code into the confirmation field. If it is about to expire, wait for the next one.
Microsoft 365 confirms that two-factor authentication is on. From now on it will ask for a code when you sign in — click the extension icon and copy it.

No QR code, or it will not scan? Look for the option to enter a key manually on Microsoft 365’s setup screen, copy the key, and add it in the extension with “Add Account” → “Manual” → “Secret Key”.

Get 2FA Authenticator for Chrome — free

Add a second sign-in method

Microsoft’s help for work or school accounts describes no backup codes. Your way back is a second method on the Security info page — a phone number, a second authenticator, or whatever else your organization offers — and, failing that, your IT help desk, which can make you register your methods again. Microsoft allows up to five authenticator apps and hardware tokens per account, so a second copy of the codes is possible; the extension’s automatic backups cover a reinstall.

The code is not accepted?

Most often the QR code changed: the website makes a new one each time its setup page is reloaded or opened again, so the account you added first no longer matches. Start the setup again, add the QR code that is on the screen now and type its code in straight away. Two entries for the same website? Use the newest. Other reasons: why codes are refused.

Typed the key in by hand? Paste it into the TOTP code generator and compare the code with the one in the extension. If they differ, the key was copied wrong — add the account again.

Questions

Do I have to use Microsoft Authenticator for my work account?: Not if your organization allows other apps. The setup screens push Microsoft Authenticator, but “I want to use a different authenticator app” accepts any app that generates standard six-digit codes, and the Authenticator extension reads the QR code straight off the Security info page. If your organization requires push notifications with number matching, those exist only in Microsoft Authenticator.
Why is there no “I want to use a different authenticator app” option?: Your organization’s administrator has not allowed third-party authenticator apps (Microsoft calls them software OATH tokens) for your account, or limits you to certain methods. Only the administrator can change that — ask your IT help desk which methods you may use.
What if I lose access to my authenticator?: Sign in with another method you added on the Security info page, delete the old authenticator there and add the new one. If you have no other method, your IT help desk can reset your sign-in methods so you can register again. With the extension, restoring one of its automatic backups on a new computer keeps the same codes working.
Is this the same as my personal Microsoft account?: No. A work or school account is managed by your organization at mysignins.microsoft.com; a personal Microsoft account — Outlook.com, Hotmail, Xbox, a personal OneDrive — is managed by you at account.microsoft.com. Each has its own authenticator setup, and the extension can hold both as separate entries.

Your codes, one click from the login page

Authenticator keeps your 2FA codes in the browser, on your device only — free to use, open source, no account and no phone needed. Local backups and optional password protection come built in.