Microsoft today began selling additional space on its OneDrive cloud-based storage service to customers who subscribe to its consumer-grade Office 365 plans.

The extra storage starts at $2 per month for 200GB and climbs to $10 per month for 1TB (terabyte). The additional support is available only to customers who already subscribe to Office 365 Personal or Office 365 Home, the two consumer-targeted plans whose primary benefit is the right to run Office on Windows or macOS.

The consumer Office 365 plans provide 1TB of OneDrive storage space for the account holder, in the case of the single-user Personal, or for each of six possible users, under Home’s rules. The additional OneDrive space would be atop the 1TB.

In fine print at the bottom of the plans’ presentation page, Microsoft said that the additional space would not be accessible to every user on an Office 365 Home plan. “For Home subscriptions, only the primary subscription holder may purchase additional storage, and only for that user’s account,” the tiny type read.

In June, Microsoft announced plans to provide supplementary storage to Office 365 Personal and Office 365 Home subscribers but did not tip to a timetable. Around the same time, Microsoft also touted something it called OneDrive Personal Vault, a protected partition for storing the most sensitive and important files. Personal Vault, Microsoft said, would be accessible only through a second step of identity verification, such as a fingerprint, face scan or one-time codes texted to the user’s smartphone.

Personal Vault has debuted in some markets, and should be available globally by year’s end, according to Microsoft. Some Computerworld staffers based in the U.S. have been offered the feature.

Microsoft’s prices for added storage are higher than its main rivals in the consumer market, Apple and Google. Both those companies lease 2TB of space for $2 per month, or twice the amount from Microsoft but for the same number of dollars.