You open Microsoft 365 Copilot in your tenant and see a “Quota exceeded” error message, even though every user who needs Copilot has an active license assigned. This error can stop your entire team from generating summaries, drafting emails, or querying business data. The root cause is not a missing license but a tenant-level service limit that Microsoft enforces to prevent runaway API consumption. This article explains why the quota error appears and provides the exact steps to resolve it by adjusting Copilot settings in the Microsoft 365 admin center.
Key Takeaways: Resolving the Copilot Quota Exceeded Error
- Microsoft 365 admin center > Copilot > Usage limits: Adjust the daily per-user request quota to a higher value or remove the cap entirely.
- Microsoft 365 admin center > Billing > Licenses: Verify that each affected user has an active Copilot license assignment and that the license count matches the number of users.
- Microsoft 365 admin center > Copilot > Data sources: Restrict Copilot to a limited set of Microsoft Graph data sources to reduce API calls per request.
Why the Quota Exceeded Error Occurs on an Active License
The “Quota exceeded” error in Copilot for Microsoft 365 is a service-side limit, not a licensing failure. When you assign a Copilot license, Microsoft grants a baseline number of API requests per user per day to the underlying Microsoft Graph and Azure OpenAI services. If your tenant exceeds this baseline due to high usage, Copilot blocks further requests until the quota resets or an admin increases the limit. The error appears even when all users have valid, active licenses because the quota is a per-tenant aggregate, not a per-license guarantee.
Microsoft sets a default daily quota per user, typically around 500 requests, but this number varies by subscription plan. When multiple users make simultaneous requests, the tenant can hit the aggregate cap quickly. The error message does not specify which user or which service triggered the limit. Admins must check the Copilot usage reports in the Microsoft 365 admin center to see the current consumption.
How the Quota Relates to Microsoft Graph and Azure OpenAI
Each Copilot request triggers calls to Microsoft Graph for data retrieval and to Azure OpenAI for natural language generation. These services have their own rate limits. If your tenant hits the Graph API limit, Copilot cannot fetch the data needed to answer a query. If the Azure OpenAI limit is reached, the model cannot generate a response. The “Quota exceeded” error in Copilot is a catch-all for either service reaching its cap. Adjusting the Copilot usage limit in the admin center raises the threshold for both services simultaneously.
Steps to Fix the Quota Exceeded Error in Copilot
Follow these steps to identify the cause and remove or increase the quota limit. You need global admin or Copilot admin privileges to change these settings.
- Open the Microsoft 365 admin center
Go to admin.microsoft.com and sign in with an account that has Global Administrator or Copilot Administrator role. - Navigate to Copilot settings
In the left navigation pane, select Settings then Org settings. Under the list of services, find and select Copilot. If you do not see Copilot listed, your tenant may not have the feature enabled for all users. Contact Microsoft support to activate it. - Adjust usage limits
Inside the Copilot settings page, click the Usage limits tab. You will see a field labeled Daily request limit per user. The default value is 500. Change this value to a higher number such as 1000 or 2000. To remove the limit entirely, set the value to 0. Click Save to apply the change. The new limit takes effect immediately for all users. - Verify license assignment
In the admin center, go to Billing then Licenses. Select the Copilot for Microsoft 365 product. Check the Assigned column to confirm that every user who needs Copilot has a license. If a user is missing a license, select the user and click Assign license. An unlicensed user can still trigger the quota error if they attempt to use Copilot, because the service counts their request against the tenant quota even if the request fails. - Restrict data sources to reduce API calls
Still in the Copilot settings page, click the Data sources tab. By default, Copilot has access to all Microsoft Graph data including emails, files, and calendars. To reduce the number of API calls per request, uncheck data sources that your users rarely need. For example, uncheck Calendar or Tasks if your team uses Copilot mainly for document summaries. Fewer data sources mean fewer API calls per request, which helps stay under the quota. - Monitor usage after the change
Return to the Copilot settings page and click the Usage reports tab. You will see a graph showing daily API requests for the last 30 days. Compare the usage after your limit adjustment. If the graph still shows spikes that approach the new limit, consider raising the limit further or restricting data sources more aggressively.
If Copilot Still Shows Quota Exceeded After the Main Fix
Sometimes the error persists even after you increase the limit. The following issues may apply to your tenant.
Copilot Returns Quota Exceeded Only for Certain Users
If only a subset of users sees the error, check whether those users have a different license SKU. For example, users with Copilot for Microsoft 365 have a higher default quota than users with Copilot Pro. If the tenant has mixed license types, the aggregate quota is calculated based on the highest license tier. Upgrade all users to the same SKU or adjust the usage limit to accommodate the lowest-tier license. To check the license SKU, go to Billing > Licenses and filter by product name.
Copilot Error Appears in Outlook but Not in Word
The quota limit applies to all Copilot surfaces, but the error may appear in Outlook first because email and calendar requests consume more API calls than document summarization. If the error is surface-specific, reduce the data sources for that surface. In the Copilot settings page, click the Surfaces tab and deselect the surfaces that are not needed. For example, turn off Copilot in Teams if your team uses it only in Word and Outlook. This reduces overall API consumption.
Copilot Error After a Tenant Migration or License Change
If your tenant recently migrated from a different subscription or you changed license plans, the quota settings may have reset to defaults. Repeat the steps in the main fix to reapply your custom usage limit. Also check that the Copilot service plan is enabled for each user. In the admin center, go to Users > Active users, select a user, click the Licenses and apps tab, and verify that the Copilot toggle is on. If it is off, turn it on and save.
| Item | Default Quota Behavior | After Quota Adjustment |
|---|---|---|
| Daily request limit per user | 500 requests | 1000 or 0 for unlimited |
| Data source scope | All Microsoft Graph data | Restricted to selected sources |
| Error message visibility | All users see the error when aggregate limit is hit | Only users exceeding their personal limit see the error |
| License requirement | Active Copilot license required per user | Same requirement, but unlicensed users also count toward quota |
The quota-exceeded error in Copilot is a manageable service limit, not a permanent block. By increasing the daily request limit in the admin center and restricting data sources to only what your team needs, you can eliminate the error for most users. If the issue persists, verify that each user has the correct license SKU and that the Copilot service plan is enabled. For tenants with very high usage, consider contacting Microsoft support to request a custom quota increase beyond what the admin center allows.