Outbound multimedia messaging services (MMS) such as pictures, videos, and other files can be sent over OpenPhone as part of our services for both local numbers and toll-free.
This can include sending JPEG, PNG, GIFs, PDFs, and several other file types. In this article, we cover the message size limitations and best practices when sending MMS messages and potential reasons that MMS may not arrive when sent to OpenPhone numbers.
MMS message size limitations
While messages on OpenPhone can be up to 5MBs total, the accepted limit from the receiving carrier may vary and cause inbound messages from OpenPhone to not arrive properly to them. Please review with your respective carriers for their inbound file size limits, as they can be different from OpenPhone.
For OpenPhone, If your message exceeds 5MBs, then your message will automatically fail due to the file size being too large for delivery on our network.
The maximum MMS attachment size varies not only based on the carrier, but also if you are messaging from a local US/Canadian number vs a toll-free number.
US or Canadian 10-digit local number MMS size limitation (subject to change by the respective carrier, please review with carrier for most accurate information):
- AT&T - 0.6MB
- T-Mobile - 1.5MB
- Verizon - 0.675MB
When messaging from toll-free numbers, there’s a standard limit of 0.6MB (or 600KB) per message. For other carriers not listed above, we recommend sending MMS attachments no larger than 0.6MB (or 600KBs) as file size limits can range between 600KB and
OpenPhone automatically resizes images that are under 5MBs but exceed the limits set by the receiving carrier. If you’re unsure of the carrier of the message recipient, we recommend sending a message no larger than 600KBs to ensure the best picture quality.
If you have any other questions, please submit a request here. We're happy to help!