Sell Outlook Data: What It's Worth to AI Companies
Thinking about whether to sell Outlook data? Get a quick estimate for your Outlook history, see what buyers pay more for, and learn how a sale works without giving up your data.
Microsoft 365 mailboxes hold years of company correspondence, and shared mailboxes like sales@ or support@ are often the most valuable part. On its own, a few hundred gigabytes over several years often estimates in the tens to low hundreds of thousands of dollars, and more alongside Teams, SharePoint and CRM data.
Estimate your Outlook data
Why AI companies want Outlook data
Many established companies, especially in construction, manufacturing, finance and professional services, have run on Outlook for a decade or more. That long history of quotes, change orders, vendor negotiations and customer service is exactly the kind of real work AI agents need to learn from.
What makes Outlook data worth more or less
| Raises value | Lowers value |
|---|---|
| A decade or more of mail | Recent mailboxes only |
| Shared mailboxes like sales@ and support@ | Mostly automated notifications |
| Former employees' mailboxes and PST archives kept | Departed users removed after the retention period |
| Teams and SharePoint in the same tenant | Email only |
| Clear ownership of the tenant | Mail held for clients under confidentiality |
What's removed or excluded
Names, addresses, phone numbers and account numbers are removed before transfer. Privileged legal mail, client-confidential material and records about individuals' health or finances are typically excluded.
How to measure your Outlook data
In the Microsoft 365 admin center, the Exchange mailbox usage report shows storage per mailbox. Add up user, shared and former-employee mailboxes, plus any old PST archives stored elsewhere.
How to sell or license it
- Don't delete anything. Keep the account active, including former employees.
- Note the size and history. Total mailbox storage from the Exchange usage report, years of mail, and any PST archives.
- Get an estimate. Use the estimator above, or the full calculator to include your other systems.
- Request an offer. A direct buyer reviews a sample, prices it, and pays after anonymized delivery. Start with Polyshares, or compare buyers first.
Common questions
Can I sell my company's Outlook email?
If the company owns the Microsoft 365 tenant and the mail is about its own operations, generally yes, under a license with identifying details removed. Exclude privileged and client-confidential mail.
Do old PST files count?
Yes. Archived PST files from former employees or earlier systems add history, which raises value.
How do I export all company mailboxes?
Through eDiscovery in the Microsoft Purview portal. The old export tool was retired in 2025. See our Outlook export guide.
Is Teams data worth anything too?
Yes. Teams chat works like Slack and is often worth as much or more than email. Include it in the full calculator.