An authenticator app is a security tool used for two-factor authentication (2FA) that enhances the security of online accounts.

You can use it to generate a temporary code, known as a Time-based One Time Password (TOTP). You then enter this in addition to your regular password to log into an account.

This extra layer of security significantly reduces the risk of unauthorised access to your accounts.

Why Use an Authenticator App?

Increased Security

Authenticator apps are more secure than other forms of 2FA like SMS, as the codes are generated on your device. This means they aren't transmitted over a mobile network, where there's a chance they could be intercepted or captured by SIM swapping attacks.

Authenticator apps can be linked to the biometric security on your device, preventing someone using it without your knowledge.

Offline Access

Authenticator apps work offline, and generate codes even when your device doesn't have an Internet connection. This is useful when you're travelling or in areas with poor network coverage.

Faster Authentication

Authenticator apps provide instant access to codes compared to waiting for SMS messages or phone calls to arrive, which can be delayed due to network congestion or other factors.

Protection Against Common Threats

They offer protection against phishing attacks and breaches that can occur due to weak or reused passwords.

Privacy

Authenticator apps don't expose your phone number. This helps to protect your privacy and reduce the risk of SIM swapping attacks or other forms of social engineering.

Widespread Compatibility

Authenticator apps are widely supported by many online services and websites. This means you can use the same app for multiple accounts, streamlining the authentication process.

How Authenticator Apps Work

TOTP Algorithm

The app uses a secret algorithm, linked to the current time, to generate a unique code every 30-60 seconds. When you log in with your username and password, you're prompted to enter the current TOTP code.

Your attempt to log in is only successful if the code you enter is correct. 

Setup Process

Typically, you can scan a QR code provided by the service you're securing. This creates a secure connection between your account and the app.

Choosing an Authenticator App

We recommend you use Microsoft Authenticator, but there are other options available that you can use. Click the links below to find out more about these apps:

• Microsoft Authenticator >
• Google Authenticator >
• Authy Authenticator >

 TIP: Look for apps that offer secure backups, compatibility with your devices, and the ability to manage multiple accounts.

How to use the Authenticator App

The set up process may vary between different apps.

Click the links below to find out how to set up the following apps. 

• How to use the Microsoft Authenticator >
• How to use the Google Authenticator >
• How to use the Authy Authenticator >

Safety Tips

• Ensure the device you install the authenticator app to is secured with a passcode or biometric lock
• Keep the QR code and the secret key secure and don't sharing them

• How to sign up to 2-factor authentication