To add another device to Duo Mobile, you must first authenticate into your organization's device management portal using an already-enrolled device. This prerequisite is critical because the portal is the only way to link a new phone or tablet to your existing Duo account for two-factor authentication, whether you are adding a second device or replacing a lost one.
Before you add another device to Duo Mobile
Before starting, understand the difference between adding a new device and reactivating on a replacement phone with the same number. Adding a new device means you keep your existing enrolled device active and simply add another one to your account. Reactivating is for when you replace your phone but keep the same phone number; in that case, you can often use a "Reactivate Duo Mobile" option in the portal instead of going through the full add-device workflow. In either scenario, you must first log into your organization's device management portal using an already-enrolled Duo device to prove your identity.
Download and install Duo Mobile on the new device
Open the Apple App Store on an iPhone or the Google Play Store on an Android device, search for "Duo Mobile," and install the app. Duo Mobile also supports other devices such as Windows Phone or tablets; for those, visit the respective app store for your device. When you launch it for the first time, grant the requested camera and notification permissions so the app can scan QR codes and send push authentication requests. The app is now ready to be activated.
Activate Duo Mobile by adding the device to your account
This merged process links the app on your new device to your Duo account. In the device management portal, choose "Add a new device," then select the operating system of your new phone or tablet. The portal will display a QR code. Open Duo Mobile on the new device and tap the option to scan a QR code, or if the portal provides an activation key, manually enter that key into the app. Once scanned or entered, Duo Mobile verifies the information and the device is activated. You can now use it to generate authentication codes and receive push requests.
Reactivate Duo Mobile if you have a new phone with the same number
If you replaced your phone but kept the same phone number, you can often reactivate Duo Mobile without going through the full add-device process. This option re-links your existing Duo account to the new device using your unchanged phone number. Note that Duo Restore can migrate accounts between devices, but it only works between devices of the same operating system (for example, iOS to iOS or Android to Android). If you are switching operating systems (such as from Android to iOS) or changing phone numbers, you must remove the old device and add the new one as a completely new device. Simply transferring app data via a migration assistant will not reactivate Duo Mobile; manual reactivation is required.
Test the new device for authentication
To confirm the new device works, initiate a login to any Duo-protected service. When prompted for two-factor authentication, open Duo Mobile on the new device. The app will display a time-based authentication code or send a push notification. Enter the code or approve the push. If the login succeeds, the new device is fully integrated and ready for everyday use.
Frequently Asked Questions
Can I have Duo Mobile on more than one device at the same time?
Yes, Duo Mobile supports multiple devices on a single account. You can add a second phone or a tablet while keeping your original device active, as long as you authenticate through the device management portal to authorize each addition.
Can I have different accounts linked to Duo Mobile on each of my devices?
Yes, you can have different accounts linked to Duo Mobile on each of your devices.
What happens to my old device when I add a new one?
Your old device remains active unless you specifically remove it from the device management portal. If you are replacing a lost or stolen phone, you should remove the old device from your account immediately to prevent unauthorized access.
Do I need to contact my IT department to add a device?
In most cases, no. Users can add or reactivate devices themselves through their organization's self-service device management portal. However, administrators can also add phones for users directly through the Duo Admin Panel if needed.
Can I set up Duo Mobile on a new phone without my old phone?
Yes, as long as you have another enrolled device (such as a tablet or a hardware token) to authenticate into the device management portal. If you have no other enrolled device, contact your organization's IT support for help recovering your account.
Is the process to set up a Duo Mobile account the same as adding a device?
No. Setting up a Duo Mobile account for the first time involves enrolling with your organization, which typically requires an invitation or administrator setup. Adding another device to an existing account is a separate, self-service process through the device management portal.
How is this different from setting up Microsoft authenticator on new phone?
While both apps serve two-factor authentication, Duo Mobile requires you to authenticate into your organization's portal using an already-enrolled device before adding a new one. Microsoft Authenticator often allows recovery through a cloud backup or alternate verification methods. Duo Restore also has a cross-platform limitation that Microsoft Authenticator does not share.
