Yes. With the Messages resource URI, you can send and receive messages containing up to 1,600 characters. These long SMS are called concatenated messages.
Sending outbound concatenated SMS
Concatenated messages are supported when sending to all major US/Canada carriers except for US Cellular, who do not support concatenated SMS. Many carriers worldwide as well as many smaller US/Canada carriers also support concatenated messages.
Historically, Sprint (US) did not support concatenated SMS. Concatenated SMS to Sprint is now supported as of March 2019. Older Sprint handsets may still be unable to display concatenated SMS, so these devices may still display long SMS as separate segments marked with "1/3", "2/3" etc.
When sending concatenated SMS, Twilio will auto-segment long messages with a special header, which mobile carriers can use to reassemble the segments on the destination handset. Thus, concatenated SMS can appear as one single message on the receiving device.
Refer to our FAQ for how pricing works for outbound concatenated messages.
Please note, when sending very long SMS messages (longer than 10 segments with Unicode characters) some mobile carriers may have trouble handling these messages. It is advisable to keep your messages shorter than 10 segments if possible.
For extensive details on how GSM vs. Unicode encoding works, and how this relates to concatenated messages, see: What the Heck is a Segment?
What happens when sending to a carrier that does not support concatenated messages?
Even if a mobile carrier does not support concatenated messages, you can still send long SMS to recipients on that carrier. Twilio will divide your long message into individual SMS to meet the character limit, and automatically add page information to the beginning of each one, for example (1/2), (2/2). On Twilio, your message will still appear under a single Message SID.
A note about US Cellular: 150-character limit
In addition to not supporting concatenated messages, US Cellular also limits the length of a single message to 150 characters, instead of 160. This means that long messages to US Cellular may segment slightly differently than those to other networks.
Receiving inbound concatenated SMS
Similarly, Twilio supports inbound concatenated messages up to 1,600 characters. Inbound messages over 160 characters long will be received on your Twilio phone number as one single message, as long as the sending carrier supports concatenation. The price of the inbound message will be the sum of the total number of segments.