Microsoft Teams file size limit: 250 GB, and why your upload still fails

The 250 GB limit comes from OneDrive and SharePoint, not from Teams, so it's the same on every Microsoft 365 plan and on Teams free. For any file larger than a few GB, Microsoft recommends uploading it with the OneDrive sync app rather than through a browser.

Where a file ends up depends on where you share it, and that decides whose storage it uses:

• In a channel: the file goes to the team's SharePoint site, in a folder for that channel. It counts toward the team's storage, which is shared across your organization.
• In a chat: the file is uploaded to a folder called Microsoft Teams Chat Files in your own OneDrive, and shared with the people in the chat. It counts toward your OneDrive storage.

You'll find every file shared in a chat or channel under its Shared tab. To send a file that's already in OneDrive, share a link to it instead of uploading it again, so you don't end up with a second copy.

Microsoft's page of Teams limits lists a file size limitation of 100 MB for chats, next to the limit of 10 attachments per message. It has been there since at least 2025, but Microsoft doesn't explain it, and many guides skip it and quote 250 GB for chats too.

The confusion comes from where chat files go: they're uploaded to your OneDrive, which takes files up to 250 GB, and a Microsoft moderator said in 2022 that chat uploads follow OneDrive's limit. To be safe, treat 100 MB as the limit for chat attachments. For anything bigger, upload the file to OneDrive and paste a link to it into the chat, or post it in a channel, where the 250 GB limit applies.

Your storage is full

A file has to fit in the storage it's going to. On Teams free, you have 5 GB for documents and other files, and once it's full you can't attach new files to messages. Photos and videos don't count toward it. At work or school, chat files use your OneDrive storage, and channel files use the storage your organization shares, so ask your IT team if a channel upload fails.

The file name isn't allowed

OneDrive and SharePoint reject some file names. Rename the file if it has:

• Any of these characters: " * : < > ? / \ |
• A space at the start or end of the name
• A reserved name, like CON, PRN, AUX, NUL, .lock or desktop.ini, or a name that starts with ~$

Some organizations don't allow # and % in file names yet either. OneDrive also refuses some types of files for security reasons, like files that Windows itself uses.

Too many files at once

You can attach up to 10 files to one chat message. To send more, zip them into one file first, or share a link to a OneDrive folder. Our guide to sending a zip file shows how to make one.

You don't have OneDrive

Sharing files in a chat needs OneDrive for work or school, which comes with a SharePoint license. If your organization doesn't use SharePoint, Microsoft says you can't share files in chats, and only sometimes in teams. That's one for your IT team.

This is where Teams trips up most people. Microsoft has two common ways to work with people from other companies, and only one of them lets you share files:

• External access: you chat with someone who uses Teams at their own company. You can chat and call, but Microsoft lists sharing files as not supported.
• Guest access: the person is invited into your organization as a guest. Guests can share files, as long as your organization allows guests, but they have to sign in to your organization with their guest account to see them.

So for a client or supplier who isn't a guest, sending the file in a Teams chat isn't an option. Share a OneDrive link if your organization allows sharing outside it, or use a service that sends a link anyone can open. Check your company's rules first, as some only allow approved tools for work files.

Share a OneDrive or SharePoint link

In Teams, open OneDrive, go to My files, hover over the file and select Share. Choose Copy link and paste it into the chat, or set who can open it first. This uploads the file once, and everyone uses the same copy.

Split files over 250 GB

Nothing over 250 GB fits in OneDrive or SharePoint as one file. Split it into parts with an app like 7-Zip, or for something this big, consider an external drive.

Send a link with VeilShare

If the file is for someone outside your organization, or your storage is full, send a link that works for anyone:

1. Drop your files or a whole folder onto the upload box on our homepage.
2. Pick how long the link should last, 6, 24, 48 or 72 hours, and add a password if wanted.
3. Click on the upload button, copy the link and paste it into your Teams chat or an email.

Your recipient opens it in any browser, without a Microsoft account, guest invite or sign-in. Files are encrypted in your browser before they're uploaded, the link stops working when it expires, and nothing is left in your company's storage. It's free up to 3 GB without an account.

Using other chat apps too? See our guides to the Discord file size limit and email attachment size limits.