---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/21661#article
headline: "21661: 'From' number is not SMS-capable"
url: https://www.twilio.com/docs/api/errors/21661
inLanguage: en
dateModified: 2026-06-08T11:38:30.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 21661: 'From' number is not SMS-capable

Log Type: APPLICATION

Log Level: ERROR

## Description

This error occurs when the value you pass in `From` is not a Twilio phone number that can send SMS. If you specify `from` in `<Message>`, it must be a message-capable local phone number assigned to your account.

### Possible causes

* The `From` value is a Twilio phone number on your account that does not have SMS capability.
* You specified `from` in `<Message>` with a phone number that is not message-capable.
* You purchased or selected a number for another use case, such as voice, without confirming that SMS is enabled for that number.

### Possible solutions

* Use a Twilio phone number that shows SMS capability and belongs to the account sending the message.
* Buy an SMS-capable Twilio phone number if your current number does not support SMS.
* If you send with a Messaging Service, add at least one phone number or channel address to the Sender Pool, ensure it is SMS-capable, and send with `MessagingServiceSid` instead of `From`.

#### Additional resources

* [Messages resource](/docs/messaging/api/message-resource)
* [Get started with Messaging Services](/docs/messaging/tutorials/send-messages-with-messaging-services)
* [Phone Numbers](/docs/phone-numbers)