> For the complete documentation index, see [llms.txt](https://docs.lightpost.app/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.lightpost.app/core-concepts/groups/messaging-policies/sms-message-length-limits.md). # SMS message length limits Lightpost uses 3rd party providers to send different types of communication to your groups. These 3rd party providers do their billing based on the 160 character [limitation of the SMS](https://www.twilio.com/docs/glossary/what-is-an-sms-short-message-service) (hence the name "Short Messaging Service"). Lightpost limits each SMS message sent to this same limitation to avoid unexpected "double message" charges. #### My other provider had a 300 character limit Some text service providers provide a "larger limit" -- however, they are still bound to this same [technical limitation](https://www.twilio.com/docs/glossary/what-sms-character-limit). Often, other services pricing per SMS message is high enough to cover the cost of a 300 character message using two SMS credits. This provider can then average the cost of other messages that stay below the 160 character limit. #### But longer messages appear as one SMS from other providers The SMS protocol does allow for "[message concatenation](https://support.plivo.com/hc/en-us/articles/360041742091-How-does-SMS-concatenation-work)", which adds special information to a series of SMS messages to make it appear as one long message on the phone for the recipient. However, the whole message is still sent using **153** character **segments** using this method, [each billed separately](https://help.twilio.com/articles/223133407-How-much-does-it-cost-to-send-a-message-with-more-than-160-characters-). #### Why doesn't Lightpost allow message segmentation? In the interest of transparency around billing, there is one text field for creating and sending [one text message](https://support.plivo.com/hc/en-us/articles/360041298072-What-is-the-character-limit-for-SMS-text-messages). This means that one message sent equals one message billed. You are free to send multiple messages one after the other, to send longer messages. Also check out [sending with MMS](/core-concepts/groups/sms-1.md) for longer messages. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.lightpost.app/core-concepts/groups/messaging-policies/sms-message-length-limits.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.