Total message size must be under 5MB. Any message with media or collection of media larger than 5MB will fail with an error. If you need to send a file greater than 5MB then we recommend storing your file online and sending a link to it instead.

* Contacts will not receive an MMS if they have MMS disabled on their mobile phone, if their mobile phone does not support MMS or if their carrier plan does not include MMS. 

The following types of content are fully supported for Media. This content will be formatted for delivery on destination devices.

The following types of content are accepted for Media, but content will not be modified for device compatibility. Some mobile devices don't support these formats and won't be able to receive or open the media. The file size limit also depends on the recipient's mobile operator. We recommend a limit of 500KB for these MIME types.

Audio