---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/21208#article
headline: "21208: Invalid Timeout"
url: https://www.twilio.com/docs/api/errors/21208
inLanguage: en
dateModified: 2025-12-18T21:40:49.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 21208: Invalid Timeout

Log Level: ERROR

## Description

You attempted to initiate an outbound phone call, but you sent an invalid Timeout parameter. The timeout specifes how long Twilio should let the phone ring before giving up, and is useful if you want to have Twilio hangup before an answering machine picks up. You may specify any positive, whole integer for the Timeout parameter.