Does one authenticator cover QuickBooks and TurboTax?

Yes, if you sign in to both with the same Intuit Account: the codes belong to the account, not to the product. If you use different user IDs for them, each is its own Intuit Account and needs its own setup. Credit Karma keeps its own login, so its security settings are separate.

Do I need a phone for Intuit’s authenticator?

For the codes, no. Intuit suggests downloading an app from the App Store or Google Play, but it only checks the six-digit code, and the Authenticator extension produces it in Chrome. Turning on 2-step verification itself does need a phone number that can receive a text or voice message.

What if I lose access to my authenticator?

Intuit does not document backup codes, so the way back is a second copy of the account in another authenticator app, the extension’s automatic backups, or account recovery through the phone number and email on the account. If you no longer have that phone number, changing it to turn 2-step verification off takes Intuit’s Proof of identity form with a copy of a driver’s license, state ID or passport.

Why does Intuit say my code is wrong?

Usually the computer clock is off by a minute or more. Turn on automatic date and time and try the next code. If it still fails, remove the account from the extension, turn 2-step verification off and on again — that also turns the authenticator off — and set the authenticator up anew.

Intuit Authenticator App — 2-Step Verification for QuickBooks and TurboTax

One Intuit Account signs you in to TurboTax and QuickBooks, so it guards your tax returns and bank details — and, for a business, its books and payroll. Intuit already asks for a code on unrecognized devices; with 2-step verification and an authenticator app on, it asks on every sign-in, and the code comes from your own device instead of a text message.

Turn on the authenticator for your Intuit Account

Intuit sets the authenticator up after 2-step verification, which first confirms your phone number with a text or voice message — have that phone at hand for the first part. Multi-factor authentication, the code Intuit sends when you sign in on a new device, is separate and cannot be turned off.

Sign in to your Intuit Account on your computer and select “Sign in & security”.
In the “2-step verification” section, select “Turn on”, then “Set up”.
Confirm your phone number, choose a text or voice message, enter the code and your password — Intuit confirms that 2-step verification is on.
Back in “Sign in & security”, select “Authenticator”, then “Set up authenticator app”.
Follow the instructions on the screen. When Intuit shows a QR code, leave that page open and add it to the extension as described below — then enter the six-digit code from the extension.

Intuit’s own instructions

Add Intuit 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 Intuit 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 Intuit and type the current code into the confirmation field. If it is about to expire, wait for the next one.
Intuit 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 Intuit’s setup screen, copy the key, and add it in the extension with “Add Account” → “Manual” → “Secret Key”.

Get 2FA Authenticator for Chrome — free

Plan a way back into your Intuit Account

Intuit’s help pages do not describe backup codes for the authenticator, so make your own way back before you need it. While the QR code is on the screen, scan it with an authenticator app on your phone as well — both will show the same codes. Keep the phone number and email address in Sign in & security current, because Intuit uses them to recover the account when you cannot sign in, and keep the extension’s automatic backups on.

The code is not accepted?

Almost always the computer’s clock. The codes are calculated from the current time, so a clock that is a minute off produces codes that look right and are refused. Turn on automatic date and time in your system settings — step-by-step for Windows, macOS and Linux.

If the clock is right, check the key itself: 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

Does one authenticator cover QuickBooks and TurboTax?: Yes, if you sign in to both with the same Intuit Account: the codes belong to the account, not to the product. If you use different user IDs for them, each is its own Intuit Account and needs its own setup. Credit Karma keeps its own login, so its security settings are separate.
Do I need a phone for Intuit’s authenticator?: For the codes, no. Intuit suggests downloading an app from the App Store or Google Play, but it only checks the six-digit code, and the Authenticator extension produces it in Chrome. Turning on 2-step verification itself does need a phone number that can receive a text or voice message.
What if I lose access to my authenticator?: Intuit does not document backup codes, so the way back is a second copy of the account in another authenticator app, the extension’s automatic backups, or account recovery through the phone number and email on the account. If you no longer have that phone number, changing it to turn 2-step verification off takes Intuit’s Proof of identity form with a copy of a driver’s license, state ID or passport.
Why does Intuit say my code is wrong?: Usually the computer clock is off by a minute or more. Turn on automatic date and time and try the next code. If it still fails, remove the account from the extension, turn 2-step verification off and on again — that also turns the authenticator off — and set the authenticator up anew.

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.