Saily phone number supports standard SMS messaging using the GSM-7 encoding standard. The character limit per SMS depends on the character set you use:
- Standard Latin characters: up to 160 characters per SMS.
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Special or non-Latin characters (e.g., Lithuanian, Polish, Japanese): up to 70 characters per SMS. In this case, a single SMS may consume 2–3 credits from your package.
When does an SMS become an MMS?
MMS (Multimedia Messaging Service) is not supported by Saily phone number. However, your device or carrier may automatically convert an SMS into an MMS in the following situations which would cause the message to fail to send:
- Multimedia content: attaching an image, video, audio file, GIF, or any other media to a message.
- Very long messages: while modern smartphones concatenate multiple SMS into one long text, some devices or carriers convert excessively long messages into a single MMS.
- Group messages: sending a text to multiple recipients at once typically triggers MMS so all members can see replies in a shared thread.
- Adding a subject line: adding a subject to a text message (similar to an email subject) forces MMS formatting.
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Sending a contact card (vCard): sharing contact information via a vCard file also requires MMS.
Since MMS is not supported, we recommended to use only plain-text SMS and avoid the scenarios listed above to ensure your messages are delivered successfully.
Additional tips
- Learn more about what Saily phone number is and how it works.
- Find out which apps support OTP and 2FA with Saily phone number.
