Outlook imposes file size limits, so sharing a large file usually means using OneDrive instead. If you’ve ever tried to attach a video, a high-res presentation, or a database to an email, you’ve likely hit the dreaded “file too large” error. This article explains exactly how to share a large file on outlook using built-in tools and a few clever workarounds.
Most Outlook versions cap attachments at 20 to 34 megabytes. That’s tiny for modern files. But you don’t need third-party apps. Microsoft gives you a simple solution right inside Outlook.
How To Share A Large File On Outlook
Microsoft designed Outlook to work with OneDrive for large files. When you attach a file over the limit, Outlook automatically offers to upload it to OneDrive and send a link instead. This keeps your email small and your recipient happy.
Method 1: Use OneDrive Directly From Outlook
This is the easiest method. It works in Outlook 2016, 2019, 2021, and Microsoft 365.
- Open a new email message in Outlook.
- Click the Attach File button (paperclip icon) in the ribbon.
- Browse to your large file and select it.
- If the file is too big, Outlook shows a message: “This file is too large. Upload to OneDrive?”
- Click Upload to OneDrive.
- Outlook uploads the file and inserts a OneDrive link in your email body.
- Add your message and send.
Your recipient clicks the link to download the file. They don’t need a OneDrive account, just a browser. The link expires after a set time or can be set to require a password.
Method 2: Upload Manually To OneDrive And Share
If Outlook doesn’t prompt you, or you prefer more control, do it manually.
- Go to onedrive.live.com and sign in with your Microsoft account.
- Click Upload and select your large file.
- Wait for the upload to finish.
- Right-click the file and choose Share.
- Set permissions: “Anyone with the link can view” or “edit.” You can also set an expiration date and password.
- Copy the generated link.
- Paste the link into your Outlook email body.
This method gives you more options. You can restrict access, set a password, or limit downloads.
Method 3: Compress The File Before Attaching
Sometimes you don’t need to share a huge file. Compressing it can bring it under the limit.
- Right-click the file and select Send to > Compressed (zipped) folder.
- Check the new file size. If it’s under 20 MB, attach it normally.
- For multiple files, zip them together into one archive.
Compression works best for text files, spreadsheets, and PDFs. Videos and images compress less, but it’s worth a try.
Method 4: Use A Third-Party File Sharing Service
If you don’t have OneDrive or need more features, use a free service. Popular options include:
- WeTransfer – Free up to 2 GB. No account needed.
- Google Drive – Free 15 GB. Works with any email.
- Dropbox – Free 2 GB. Share via link.
- SendAnywhere – Free up to 10 GB. Direct transfer.
Upload your file, get a link, and paste it into your Outlook email. Most services let you set an expiration date.
Method 5: Split The File Into Smaller Parts
For extremely large files, split them into chunks. Use a tool like 7-Zip or WinRAR.
- Install 7-Zip (free) or WinRAR.
- Right-click the file and choose Add to archive.
- Under “Split to volumes,” enter a size like 10 MB or 15 MB.
- The tool creates multiple archive files.
- Attach each part to a separate email. Label them clearly: “Part 1 of 4,” etc.
- Your recipient must download all parts and extract them together.
This method is old-school but works. It’s best for one-time sharing when other options fail.
Understanding Outlook File Size Limits
Different Outlook versions have different limits. Here’s a quick breakdown:
- Outlook.com (free) – 20 MB per attachment.
- Outlook 2016, 2019, 2021 – 20 MB default, but can be changed by your IT admin.
- Outlook for Microsoft 365 – 20 MB default, but OneDrive integration is seamless.
- Exchange Server (corporate) – Usually 10 MB to 35 MB, set by your company.
If you’re in a corporate environment, your IT team might have set a lower limit. Check with them before trying workarounds.
Why Outlook Has File Size Limits
Email was designed for text, not large files. Sending a 100 MB attachment clogs mail servers, slows down delivery, and fills up inboxes. Most email providers reject messages over their limit. Outlook’s limit protects everyone.
Using a link instead of an attachment bypasses these issues. The file stays in the cloud, and the email remains small.
Tips For Sharing Large Files Safely
Security matters when sharing files. Follow these best practices:
- Set an expiration date on your shared link. OneDrive and most services let you do this.
- Require a password for sensitive files. OneDrive offers this in the sharing settings.
- Don’t share personal data via unsecured links. Use encrypted services if needed.
- Check the recipient’s email before sending. A typo could send your file to a stranger.
- Use “View only” permissions for files you don’t want edited.
What If Your Recipient Can’t Open OneDrive Links?
Some companies block OneDrive links. If that happens, try:
- Using a different service like Google Drive or WeTransfer.
- Compressing the file further.
- Splitting the file into smaller emails.
- Asking your IT team to whitelist OneDrive.
Most recipients can open OneDrive links in any browser. They don’t need a Microsoft account.
How To Share A Large File On Outlook For Mac
Outlook for Mac works similarly. The OneDrive integration is built in.
- Open Outlook and create a new email.
- Click the Attach button (paperclip).
- Select your large file.
- Outlook prompts you to upload to OneDrive. Click Upload.
- A link appears in your email. Send as usual.
If you don’t see the prompt, drag your file into the email body. Outlook automatically uploads it to OneDrive.
How To Share A Large File On Outlook Web
Outlook on the web (outlook.com) also supports OneDrive sharing.
- Log in to outlook.com.
- Click New message.
- Click the Attach icon (paperclip).
- Select your file. If it’s over 20 MB, Outlook says “This file is too large.”
- Click Upload to OneDrive.
- The file uploads and a link is inserted.
You can also drag and drop files into the email. Outlook handles the rest.
Frequently Asked Questions
What Is The Maximum File Size I Can Attach In Outlook?
Outlook’s default attachment limit is 20 MB for most versions. Some corporate accounts allow up to 35 MB. For larger files, use OneDrive or another sharing service.
Can I Send A 100 MB File Via Outlook?
Not as a direct attachment. But you can upload it to OneDrive and send a link. That’s the official Microsoft solution for large files.
Does OneDrive Compress Files When I Share Them?
No. OneDrive stores the original file. The recipient downloads the exact file you uploaded. No compression happens.
How Long Does A OneDrive Share Link Last?
By default, OneDrive links don’t expire. But you can set an expiration date in the sharing settings. Choose from 1 day to 30 days, or no expiration.
Can I Share A Large File Without OneDrive?
Yes. Use third-party services like WeTransfer, Google Drive, or Dropbox. Upload the file, get a link, and paste it into your Outlook email.
Final Thoughts On Sharing Large Files In Outlook
Sharing a large file in Outlook is straightforward once you know the tricks. The built-in OneDrive integration is the best option for most people. It’s secure, easy, and doesn’t require extra software.
If OneDrive isn’t available, compress the file, split it, or use a third-party service. Each method has its pros and cons, but all of them work.
Remember to always consider security. Set passwords and expiration dates for sensitive files. And double-check the recipient’s email address before hitting send.
Now you know exactly how to share a large file on outlook. Next time you hit that size limit, you won’t panic. You’ll just upload to OneDrive and send the link. Simple.
If you run into trouble, revisit the steps above. Each method is tested and reliable. Happy sending.