Email attachment size limits, and what to do when you hit them

Attachment limits by provider

• Gmail (personal accounts): 25 MB. Google says that if your attachments are bigger, Gmail removes them and inserts a Google Drive link instead.
• Outlook: Microsoft’s Outlook guidance gives a 20 MB limit for internet email accounts such as Outlook.com, and a default of 10 MB for Exchange (business) accounts, though administrators can change it.
• iCloud Mail: 20 MB per message, or up to 5 GB with Mail Drop turned on, which uploads the attachment to iCloud and sends a link that works for 30 days.
• Work and school accounts: set by your administrator, and often lower than the consumer limits.

Why a file under the limit can still bounce

Attachments are encoded as text before they’re sent, which makes them roughly a third bigger in transit. A 19 MB file can become a 25 MB message. On top of that, the recipient’s server applies its own limit: Gmail may accept your 24 MB email, but a company server that only takes 10 MB will reject it.

What to do when your attachment is too big

1. Make the file smaller. Compress images, reduce a PDF, or zip a folder. See how to compress files for sharing.
2. Send a code instead of an attachment. Upload up to 100 MB to ShareQuik and put the 8-character code in your email. The recipient enters it on ShareQuik to download. Send files without email explains how.
3. Use your provider’s cloud link. Gmail’s Drive link, OneDrive sharing in Outlook, or Mail Drop in iCloud all work if you already use those services.
4. Use a large-file transfer service for files of several gigabytes. See how to send large files.