Microsoft announced on August 30, 2018 that starting on October 2, 2018 users with a subscription to Office 365 Home or Office 365 Personal:  “subscribers can install Office on an unlimited number of devices—and be signed into their accounts on up to five of those devices at the same time.”

Users with Office 365 Home will have up to 6 user licenses meaning up to 6 family members can have their own OneDrive storage account with 1TB of storage. This is an increase from the 5 that were originally included with Office 365 Home. “The Office 365 Home subscription is already an incredible deal. For just $99.99 a year, five people can get their own licenses to Word, Excel, PowerPoint, Outlook, and OneNote—plus 1 TB of OneDrive cloud storage and other valuable apps and services. Starting October 2, we’re increasing the number of licenses in a Home subscription from 5 to 6. That’s right: we’re adding an additional person to the subscription with no change in price. To be clear, that’s 6 people with their own license and 1 TB of OneDrive cloud storage each—for a total of 6 TB. We’re also integrating the Home subscription more deeply into the Microsoft family service, so your subscription will automatically be shared with the people you’ve set up as members of your family.”

Wish to read more details on this see this Microsoft blog article