Microsoft Copilot Conversation Log Retention Periods Explained

Microsoft Copilot stores your conversation logs to improve the service and provide continuity across sessions. Many business users are unsure how long these logs are kept or how to delete them. The retention period depends on the license type and the specific Copilot service you use. This article explains the default retention periods for Copilot with commercial data protection, Copilot Pro, and Copilot for Microsoft 365.

You will learn the exact time frames for log storage, where logs are stored, and how to manage or delete your conversation history. Understanding these policies helps you comply with your organization’s data governance requirements.

How Copilot Conversation Log Retention Works

Copilot conversation logs contain the text of your prompts and the AI-generated responses. These logs are used to improve the model, provide context for follow-up questions, and troubleshoot issues. The retention period varies by service because each one has different data handling policies tied to the underlying Microsoft 365 tenant or personal account.

Copilot with Commercial Data Protection

This free version is available to users who sign in with a work or school Microsoft Entra ID account. Microsoft does not retain conversation logs beyond 24 hours after the last interaction. After 24 hours of inactivity, the log is permanently deleted. This policy is designed to minimize data exposure while still allowing basic session continuity.

Copilot Pro

Copilot Pro is a personal subscription for individuals. Microsoft retains conversation logs for up to 90 days from the date of the last message in the conversation. You can manually delete individual conversations at any time through the Copilot web interface. If you delete a conversation, it is removed from your history immediately and cannot be recovered.

Copilot for Microsoft 365

Copilot for Microsoft 365 is an enterprise add-on that integrates with Microsoft 365 apps and the Microsoft Graph. By default, conversation logs are retained for 30 days. Tenant administrators can adjust this retention period using Microsoft 365 compliance policies. Logs are stored in the user’s Exchange Online mailbox as part of the Conversation History folder. This means retention is also governed by your organization’s existing mailbox retention policies.

How to Check or Change Your Copilot Conversation Log Retention

The steps to view or modify retention depend on your Copilot version. For enterprise users, only tenant admins can change the default 30-day retention period. Individual users can delete conversations manually but cannot change the retention policy.

For Copilot with Commercial Data Protection

1. Open Copilot in your browser
   Go to copilot.microsoft.com and sign in with your work or school Entra ID account.
2. Open the conversation history
   Click the clock icon in the top-left corner to view your recent conversations.
3. Delete a conversation manually
   Hover over a conversation entry, click the three dots, and select Delete. Deletion is immediate.

Retention is automatic. You do not need to take any action for logs to be removed after 24 hours.

For Copilot Pro

1. Sign in to Copilot Pro
   Go to copilot.microsoft.com and sign in with your personal Microsoft account.
2. Open the chat history
   Click the clock icon in the top-left corner to see all saved conversations.
3. Delete a conversation
   Hover over the conversation, click the three dots, and select Delete. The log is removed immediately.
4. Clear all history
   Click the three horizontal lines in the top-right corner, select Settings, then Privacy, and choose Clear all chat history. This deletes all logs instantly.

Logs older than 90 days are automatically purged. You cannot extend this period.

For Copilot for Microsoft 365

Only a tenant administrator can change the retention policy. Individual users can delete conversations from their history, but the log may still exist in the mailbox until the retention period expires.

1. Go to the Microsoft 365 admin center
   Sign in at admin.microsoft.com with a Global Admin or Compliance Admin role.
2. Open Compliance policies
   Navigate to Compliance > Data lifecycle management > Microsoft 365.
3. Locate the Copilot retention policy
   Look for a policy named Copilot for Microsoft 365 or Chat retention. If none exists, create a new retention label for the Conversation History folder.
4. Set the retention period
   Choose a duration between 1 day and 365 days. Apply the policy to the Exchange Online mailbox of each user.
5. Wait for policy propagation
   Changes take up to 24 hours to apply to all mailboxes.

Common Misunderstandings About Copilot Log Retention

Deleting a Conversation Does Not Delete the Log Immediately in All Versions

In Copilot with commercial data protection, deleting a conversation removes it from your view. However, Microsoft may retain the log for up to 24 hours for diagnostic purposes. In Copilot for Microsoft 365, deleting a conversation from the chat interface removes it from the chat list, but the log remains in the Exchange Online mailbox until the mailbox retention policy deletes it.

Retention Policies Override Manual Deletion in Enterprise Versions

If your organization has a litigation hold or a longer mailbox retention policy, Copilot logs stored in the Conversation History folder may be preserved even after the default 30-day period. Manual deletion by the user does not bypass these holds.

Copilot Logs Are Not Stored in Microsoft 365 Audit Logs

Conversation logs are not automatically included in the Microsoft 365 unified audit log. If your organization needs to audit Copilot usage, you must enable the Copilot activity report in the Microsoft 365 admin center under Reports > Usage > Copilot for Microsoft 365.

Copilot with Commercial Data Protection Does Not Support Extended Retention

You cannot change the 24-hour retention period for this free version. If you need longer retention, upgrade to Copilot Pro or Copilot for Microsoft 365.

Copilot Conversation Log Retention Periods: Version Comparison

Item	Copilot with Commercial Data Protection	Copilot Pro	Copilot for Microsoft 365
Default retention period	24 hours after last activity	90 days	30 days
Configurable by user	No	No	No
Configurable by admin	No	No	Yes, up to 365 days
Manual deletion available	Yes, immediate removal from UI	Yes, immediate removal from UI	Yes, but log remains in mailbox until policy deletes it
Storage location	Microsoft servers (no user access)	Microsoft servers (no user access)	Exchange Online mailbox, Conversation History folder
Compliance hold override	No	No	Yes, litigation hold or mailbox retention policy can extend retention

This table shows the key differences between the three Copilot versions. The storage location is the most important factor for enterprise compliance because it determines how logs are affected by your organization’s existing data governance policies.

What to Do If You Need to Keep Copilot Logs Longer

If your organization requires longer retention for compliance or auditing, follow these steps:

1. Use Copilot for Microsoft 365
   Only this version supports configurable retention through tenant policies.
2. Set a custom retention label
   In the Microsoft 365 compliance center, create a retention label for the Conversation History folder with the desired duration, then publish it to all users.
3. Enable Copilot activity reporting
   Go to Reports > Usage > Copilot for Microsoft 365 and turn on the activity report to capture usage data separately from conversation logs.
4. Export logs manually
   Users can copy their conversation text and paste it into a document or email before the retention period expires. This is not automated.

Longer retention is not available for Copilot with commercial data protection or Copilot Pro. If you need logs beyond 90 days, migrate to Copilot for Microsoft 365 and configure a retention label of 365 days.

Now you know the exact retention periods for each Copilot version and how to change them for enterprise deployments. To verify your current retention policy, check the Microsoft 365 compliance center or contact your tenant administrator. For Copilot Pro users, remember that manual deletion is the only way to remove logs before the 90-day auto-purge.