---
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"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/21201#article
headline: "21201: No Called number specified"
url: https://www.twilio.com/docs/api/errors/21201
inLanguage: en
dateModified: 2025-12-18T21:40:49.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 21201: No Called number specified

Log Level: ERROR

## Description

You attempted to initiate an outbound phone call, but you did not specify what number to call in the 'To' `POST` parameter