OneDrive File Size Limit: Max Upload Size (2026)
OneDrive allows a single file as large as 250 GB on both personal and business plans (as of 2026, raised from the older 100 GB cap). Separately, the full file path can’t exceed 400 characters and any single file or folder name can’t exceed 255 characters. Here’s how the limits interact and what trips people up.
The Limits at a Glance
Single file upload
- 250 GB maximum per file (personal and OneDrive for Business)
Path length
- 400 characters total for the decoded folder path plus file name combined
File or folder name
- 255 characters maximum for any single name
Invalid characters
- File and folder names can’t contain:
" * : < > ? / \ | - Names can’t start or end with a space, or end with a period
File Size vs. Storage Quota
The 250 GB number is the cap on any one file. It’s separate from your total storage quota (5 GB free, 1 TB on Microsoft 365 Personal, and so on). A 250 GB file still has to fit inside your overall quota — so on a 5 GB free account you obviously can’t upload it. See the OneDrive storage limit guide for the quota tiers.
Why the Path Limit Bites
The 400-character path limit applies to the entire decoded path — every folder name plus the file name added together. Deeply nested folders with long descriptive names hit this long before any single name reaches 255 characters. Note also that Microsoft Office apps and Windows have their own lower local path limits (historically ~259 characters), and the Windows long-paths registry setting does not help because Office doesn’t honor it. So even though OneDrive’s cloud service accepts 400, syncing those files locally can still fail.
How to Upload Large or Long-Named Files
- Upload through the OneDrive web app or sync client rather than email — both support the full 250 GB ceiling; email attachments are tiny by comparison.
- Shorten folder paths — move deeply nested files closer to the root, or shorten folder names, to stay under 400 characters.
- Rename files to remove invalid characters (
" * : < > ? / \ |) and leading/trailing spaces. - Compress to a single archive if you’re moving many small files with long combined paths — one
.ziphas one path. - Check your remaining quota before a large upload so the file actually fits.
Troubleshooting
What is the maximum file size for OneDrive?
250 GB for a single file, on both personal and business plans as of 2026 (up from the previous 100 GB cap).
Why won’t my file upload to OneDrive?
Common causes: the file exceeds 250 GB, the full path is over 400 characters, the name has invalid characters, or you’re out of storage quota. The error message usually names which one.
What is the OneDrive file path character limit?
400 characters for the entire decoded path (all folder names plus the file name combined). A single name can be up to 255 characters.
What characters are not allowed in OneDrive file names?
" * : < > ? / \ | are not allowed, and names can’t begin or end with a space or end with a period.
Does the 250 GB limit apply to free OneDrive accounts?
The per-file cap is 250 GB on free accounts too, but the file still has to fit within your 5 GB free quota — so in practice the quota is the binding limit.
Quick Reference
| Limit | Value |
|---|---|
| Max single file | 250 GB |
| Max path length | 400 characters |
| Max name length | 255 characters |
| Invalid characters | `” * : < > ? / \ |
If wrangling large files and attachments across folders is a daily chore, an AI assistant like Carly can route attachments into the right OneDrive folders from your inbox — see the OneDrive integration.
Related guides: OneDrive storage limit · Outlook attachment size limit · Dropbox storage limit · Google Drive storage limit
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