Since launching Office 365 to consumers, we have heard feedback from customers about the challenges in installing and using their office subscription across multiple devices. The first step in addressing this issue happened in October 2018, increasing a single user’s device limits to five (meaning they can concurrently use five devices) for Office 365 Home and Office 365 Personal. Our next step in simplifying use across multiple devices will streamline the activation of a user’s device.

Beginning in May, we rolled out the following changes to customers on PCs, followed by Mac devices in July.

For customers, here’s what stays the same:

• Sign in to activate Office: Users will continue to sign in to activate Office on their devices. When single sign-on is enabled, Office detects the user’s credentials and activates Office automatically.
• Sign-in limits: Users will be able to install Office 365 on all their devices and be signed in to five at the same time. This includes any combination of PCs, Macs, tablets, or phones.

It’s important to stay signed in while you use Office on your device. This is what keeps your Office installation activated and ready to use.  

Here are the changes that you may notice:

• No more prompts to deactivate: Users can install Office on a new device without being prompted to deactivate Office on another device.
• Automatic sign-out: When a user reaches the sign-in limit (five devices), instead of being prompted to deactivate, the user will be automatically signed out of Office on the device where Office has been least recently used. The next time the user starts Office on that device, the user will be prompted to sign in to activate Office.

For more information on how sign-in works on devices where Office 365 is licensed, please visit this support article: https://support.office.com/en-us/article/how-sign-in-works-in-office-365-1d646e83-1585-4278-8daf-d4a2cc0905e0