Phone System · 1 min read
Attachment Size Limits for SMS/MMS and Email
SMS vs. MMS
SMS is text only. When you add supported media to a text, it's sent as MMS. Commonly supported image types for MMS are JPEG, PNG and GIF. Other file types such as MP3, MP4 and PDF may be sent as a link instead, depending on the destination carrier.
MMS size limits
Carriers limit MMS size, and many handsets only receive small files reliably. Limits vary by carrier and number type. For the broadest compatibility, keep direct MMS attachments under 500 KB. If a file is too large for direct MMS delivery, it's uploaded to your Media Library and sent as a link in the message.
Email attachment limits
Email attachments have a total size limit per message. If attachments exceed the limit, the files are stored in the Media Library and added to the email as links instead of attachments.
Best practices
- Compress images before you send them.
- Send PDFs and videos as links rather than attachments.
- Test with your own phone or inbox before a bulk send.
- Remember that some international carriers don't support MMS at all.