Key takeaways
- Teams shows message counts in the Microsoft 365 admin center under Reports > Usage > Microsoft Teams > User activity, but only for the last 180 days at most, so an all-time total comes from a full export.
- An admin with eDiscovery permissions and a Microsoft 365 Enterprise E3 or E5 license exports full history from the Microsoft Purview portal, and the packages must be downloaded within 14 days.
- Developers can use the Teams Export APIs for JSON, but deleted messages stay reachable for only 21 or 30 days, and files shared in Teams live in OneDrive and SharePoint instead.
- You don't need to export anything to apply: have your message count, years of history and seat count ready, and the data vendor anonymizes the records before any AI lab sees them.
01
What is Microsoft Teams data, and why do AI labs and data vendors buy it?
The short answer
Microsoft Teams data is the written history of a company's working conversations in Teams: chats between people, posts and replies in team channels, reactions, mentions and the links to files they share. AI labs (companies that build and train AI models) and data vendors (companies that anonymize business records and package them for those labs) buy a copy because a Teams conversation keeps a question, the replies and the decision together, next to the files and meetings it is about.
What a Teams account records
Teams is Microsoft's workplace messaging and meeting app, and most Microsoft 365 business subscriptions include it. A company's tenant is its own private area inside Microsoft 365, and every person, team and message in the company's Teams lives there. A team is a group of people who work together, such as the sales department, and it is divided into channels, which are shared rooms organized by topic or project.
People also write to each other outside channels, in one-to-one chats and group chats. Over the years a tenant builds up all of these messages, along with the replies, @mentions and emoji reactions people add and the files they attach.
Why a Teams conversation teaches an AI model something
An AI model learns by studying a very large number of examples and finding the patterns in them, and those examples are called training data. Public text shows finished results, such as a published article, but it rarely shows how a team coordinated its work to reach them. A Teams channel shows that coordination: someone posts a problem, colleagues reply with suggestions, and a decision is made.
Every post, reply, mention and reaction is stamped with the team, the channel and the time it belongs to. Channel conversations also sit next to the files and meetings they discuss, so a lab can follow one project across messages, documents and meeting chat. Why AI companies want your data explains the demand in more detail.
How Teams fits into a dataset
Teams history is priced as one part of a whole dataset, not on its own. micro1, the data vendor we typically refer companies to, pays them $100K to $2M or more per dataset, and the figure depends on the years of history and how completely the records show each job.
A company that runs on Microsoft 365 usually holds related records in several places: this page covers the chat, while SharePoint, OneDrive and Teams meeting recordings each have their own page, and the Microsoft 365 overview shows how they connect. What your data is worth explains how the pieces add up.
02
Where does Microsoft Teams show how much data you have?
The short answer
Teams shows message counts in the Microsoft 365 admin center, under Reports > Usage > Microsoft Teams, on the User activity tab. The report covers the last 7, 30, 90 or 180 days, so the most it can show is 180 days of activity. For an all-time count, add up the items in a full eDiscovery export.
How to read your message count
The steps below read the size of a tenant from Microsoft's own usage report. Each step names the menu you need, as Microsoft's Teams user activity report guide lays out.
- Open the Microsoft 365 admin center and sign in as an admin whose role allows usage reports, for example Reports Reader or Teams Administrator.
- Choose Reports > Usage from the left menu. When Reports isn't listed, choose Show all to expand the menu.
- On the Usage page, choose Microsoft Teams, switch to the User activity tab and pick 180 days as the period.
- Choose Export to save the table as a CSV file, then total its Team Chat Message Count and Private Chat Message Count columns. Together they give the channel messages and chat messages for the period.
- The Teams admin center offers the same figures under Analytics & reports > Usage reports, in its Teams user activity report.
What the columns and roles mean
The exported file has one row per person. Three columns matter for sizing, and they are described in the table below.
| Column in the export | What it counts |
|---|---|
| Team Chat Message Count | Unique messages the person posted in team channels in the period, including original posts and replies. |
| Private Chat Message Count | Unique messages the person posted in one-to-one and group chats in the period. |
| Is Licensed | Whether the person holds a Teams license, which is a good guide to your seat count. |
Microsoft lets these roles open usage reports: Global Administrator, Exchange Administrator, SharePoint Administrator, Teams Administrator, Teams Communications Administrator and Reports Reader (the usage reports overview lists a few more). By default, reports hide user names. A Global Administrator can change that under Settings > Org Settings > Services > Reports by clearing Conceal user, group, and site names in all reports, and hidden names do not change the message totals.
Why the report is not an all-time total
The report stops at 180 days, so it describes how busy the tenant is now rather than how much it has written since it began. It also counts only what people do in the Teams app, and it leaves out posts that apps and integrations add to a channel. A figure for six months says little about a tenant that has used Teams for four years.
To estimate a longer history, divide the 180-day channel and chat total by six to get a monthly rate, then multiply by the months Teams has been in use. Label the result as an estimate. A full eDiscovery export gives a closer count, because its overview shows the number of items collected.
03
What should you know about your Teams data before you apply?
The short answer
Have three facts ready: how many messages your tenant holds, how many years it covers and how many people use Teams. They go into the data manifest, the written summary of which apps hold your records, how many years each covers and roughly how much. You don't need to run an export to find them.
The message count
The unit for Teams is messages. Use the 180-day total from the usage report scaled to your years in use, as described above, and say that it is an estimate. If you have already run a Purview eDiscovery export, use the number of items collected instead.
The years of history
The years of history run from the date your company started using Teams, or from the oldest message an eDiscovery search returns. A retention policy, which is a company rule that deletes messages after a set time, can remove older messages, so the oldest message you can find may be newer than your start date.
The number of seats
Seats are the people who use Teams. Count the rows where Is Licensed is selected in the User activity export. The Microsoft 365 admin center also lists assigned Teams licenses under Billing > Licenses.
What you don't need to do first
You don't need to export anything to apply, and you don't need to clean or scrub an export. The data vendor anonymizes the records before anyone else sees them, and nothing moves until a lawyer-reviewed license is signed. The application, the intro call and each later step are laid out in how to sell your company's data.
04
How do you export your full Microsoft Teams history?
The short answer
An admin with eDiscovery permissions and a Microsoft 365 Enterprise E3 or E5 license runs a search in the Microsoft Purview portal under eDiscovery > Cases, then exports it and downloads the packages within 14 days. A developer can instead call the Teams Export APIs in Microsoft Graph, which return messages as JSON. Files shared in Teams are stored elsewhere and are not part of the message export.
Who can run an export
The person running an eDiscovery export needs eDiscovery permissions, which an admin grants by adding them to the eDiscovery Manager role group under Settings > Role groups in the Microsoft Purview portal, plus a Microsoft 365 Enterprise E3 or E5 license. Microsoft's guide to exporting eDiscovery search results states the license rule. Premium eDiscovery features carry extra license requirements for the people whose data is collected.
The Teams Export APIs have different requirements: an active Teams license for each user whose messages are exported, and application permissions that an administrator approves.
The eDiscovery steps
eDiscovery is Microsoft's tool for searching a company's records and collecting them for legal and compliance work. These steps use it to collect every Teams message.
- Check that the account doing the export holds eDiscovery permissions and a Microsoft 365 Enterprise E3 or E5 license.
- Open the Microsoft Purview portal, choose the eDiscovery card and then Cases, and either start a new case or open an existing one.
- Go to the Searches tab and build a search that covers all people and groups, restricted to Teams content and the whole date range you want, then run it.
- Open the finished search and choose Export. Among the tenant-wide source options, tick shared Teams channels and departed users. Pick Organize conversation into HTML transcript so conversations arrive as threads, and pick Create PSTs for messages.
- Follow the job in Process manager. When it finishes, open the export's Overview tab, select its packages and choose Download packages, which has to happen within 14 days.
For a large tenant, run Generate statistics on the search first. Microsoft says this lets the export process only the locations that have results, which makes a big export faster and more reliable.
Where Teams keeps the messages an export collects
Teams stores its messages in Azure Cosmos DB, which is Microsoft's cloud database service. It also saves compliance copies in hidden folders of Exchange Online mailboxes, and eDiscovery searches those copies, as Microsoft's page on finding content in Teams with eDiscovery explains.
Where a copy lands depends on the kind of conversation. Chats are copied into the mailbox of every participant, whereas standard channel messages are copied into the mailbox that belongs to the team. The files people share are stored apart from the messages: a file shared in a chat sits in the sharer's OneDrive, and a file shared in a channel sits in the team's SharePoint site.
Private channels and shared channels (channels that include people from other organizations) work differently, because each has its own SharePoint site and its own mailbox arrangement. If your tenant uses them, Microsoft's page on private and shared channels says which mailboxes to search.
What the export files look like
An eDiscovery export produces PST or .msg files inside ZIP packages. A PST file is the archive format Outlook uses for mailbox items, and you can open it in Outlook to read the conversations. You set the size of each package: the maximum PST size can be anything from 1 GB to 10 GB, and the maximum ZIP size anything from 2 GB to 40 GB.
An export that runs for more than seven days is cancelled automatically, so split a large tenant into several exports by date range. Microsoft deletes search export packages 14 days after you create them, and an expired export cannot be recovered, so download everything inside that window.
The Teams Export APIs route
The Teams Export APIs in Microsoft Graph, Microsoft's programming interface for its cloud services, export one-to-one, group, meeting-chat and channel messages as JSON. JSON is a plain-text format that software reads easily, and these exports include reactions and attachment information. The Teams Export APIs guide lists what is supported.
An administrator must approve three application permissions for the program that makes the calls: Chat.Read.All for chats, ChannelMessage.Read.All for channel messages and User.Read.All for the list of users. If you call the API once for every user, a chat shared by several people comes back several times, since each participant's copy is exported separately. Filter by sender to avoid the repeats.
How long deleted messages stay exportable
Deleted content stays reachable through the Export APIs for a short time. A retention policy or a hold, which are company rules that keep content for a set time, can extend that time.
| What was deleted | Still exportable for |
|---|---|
| A message deleted by a user | 21 days after deletion |
| Messages from a deleted team or channel | 30 days after deletion |
| Messages from a deleted or inactive user | 30 days after the user was deleted or became inactive |
What a Teams export leaves out
A message export carries attachment references, not the files. To collect them, add the senders' OneDrive accounts and the teams' SharePoint sites to the search, or select the option to collect cloud attachments (Access links (cloud attachments) in messages) when you export. Microsoft notes that this makes the export larger.
Meeting recordings are separate files as well, and Teams meeting recordings covers how to find and export them.
How long an export takes
Microsoft gives no fixed time, and larger exports take longer. You can watch progress on the export's page in Process manager. Start early, and plan for several date-range exports if the tenant is large.
Sources: Microsoft Learn, Microsoft Teams user activity report, Export search results in eDiscovery, Finding content in Microsoft Teams in eDiscovery and Export content with the Microsoft Teams Export APIs. Steps checked against these pages in November 2026.
05
What stays private when Teams data is licensed?
The short answer
The company decides which teams, mailboxes and date ranges go into the search, and the data vendor replaces names and other personal details with consistent stand-ins before an AI lab sees anything. The company keeps ownership of its Teams history, and the license covers defined records for a defined use.
You choose what is in scope
An eDiscovery search only collects the mailboxes, teams and date ranges you put into it. A company can leave one-to-one chats out entirely and license only channel posts. The data vendor also deletes records too sensitive to clean safely instead of anonymizing them.
Names are replaced before a lab sees them
Anonymization means replacing every detail that identifies a person, such as a name or an email address, with a stand-in that is the same every time it appears. The conversation still reads in order, so a lab can learn from it, but it no longer says who the people are. The diagram below shows one channel thread before and after.
The method, including what is deleted outright and how you review samples, is in how company data is anonymized for AI training.
Ownership and payment
Licensing gives the buyer limited rights to a copy, while the company keeps ownership of the originals. The terms that matter, such as exclusivity, permitted use and deletion, are covered in data licensing. micro1 pays in full within 30 days of accepting the data, usually as a single payment.
Questions
Frequently asked questions
Can we see Teams message counts from before the last 180 days?
No. The usage reports in the Microsoft 365 admin center cover the last 7, 30, 90 or 180 days. For older history, run a Microsoft Purview eDiscovery search or use the Teams Export APIs.
Which license lets someone export Teams chats through eDiscovery?
The person running the export needs eDiscovery permissions and a Microsoft 365 Enterprise E3 or E5 license, according to Microsoft. Microsoft's premium eDiscovery features add license requirements for the people whose data is being collected.
Are files shared in Teams chats included in the export?
No. Messages point to their attachments, but the files themselves sit in OneDrive (for chats) and SharePoint (for channels). Include those locations in the search or tick the cloud attachments option at export.
Where does Teams actually store our chat messages?
The messages themselves are held in Azure Cosmos DB, Microsoft's cloud database. For compliance, Teams also writes copies into hidden folders of Exchange Online mailboxes: chats go to every participant's mailbox and channel posts to the team's, and those copies are what eDiscovery searches.
Why can't we see people's names in the Teams report?
Microsoft hides user names in usage reports by default. A Global Administrator can show them under Settings > Org Settings > Services > Reports by clearing the conceal setting, and the message totals are the same either way.
Do we need to export Teams before we apply?
No. The application takes about two minutes and shares no data. You only need your approximate message count, your years of history and your seat count for the intro call, and you can estimate the first from the usage report. The full export is needed later, when the records are transferred after you sign the license.
Can we license channel posts and leave out private chats?
Yes. You choose the mailboxes, teams and date ranges that go into the eDiscovery search, so one-to-one chats can stay out of the export completely.
What is Teams data worth to AI labs and data vendors?
Teams history is priced as part of a whole dataset rather than on its own. Companies are paid $100K to $2M or more per dataset, according to micro1, and the price depends on the years of history and how completely the records show each job. What your data is worth explains the factors.
Bottom line
Know what is in Microsoft Teams, then see what it is worth
You don't need to export anything to apply. Apply in two minutes, describe your records on the intro call, and micro1, the data vendor we typically refer companies to, prices the whole dataset and sends an offer 1–2 days later.
Not legal, tax or financial advice. Figures come from micro1's published pages and public reporting as of November 2026.