What does Twilio error 30003 mean?

Error 30003 (Unreachable destination handset) is a Messaging delivery error meaning the carrier could not reach the recipient's phone — it may be powered off, out of coverage, or the number is unable to receive SMS. It is a final delivery status, not an API request error.

What is the difference between Twilio errors in the 21xxx and 30xxx ranges?

21xxx errors are REST API request errors returned synchronously when you call the API with invalid parameters, such as 21211 (invalid To number). 30xxx errors are asynchronous message-delivery errors reported later via status callbacks, such as 30007 (carrier filtering) or 30003 (unreachable).

How do I fix Twilio error 11200?

Error 11200 (HTTP retrieval failure) means Twilio could not fetch your TwiML from the URL you configured. Check that the webhook URL is publicly reachable, returns HTTP 200 with valid TwiML, responds within Twilio's timeout, and uses a valid TLS certificate.

What causes error 30007 carrier filtering?

Error 30007 (Message blocked by carrier) means a US carrier's spam/content filter blocked the message. Common triggers are unregistered A2P 10DLC traffic, prohibited content, URL shorteners, or high opt-out rates. Register your 10DLC campaign and clean up message content to resolve it.

Is anything I search uploaded?

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What is the Twilio Error Codes Reference?

A searchable reference for Twilio error and warning codes across the REST API, Messaging, Voice, Verify and Video products — each with its product area, meaning and how to resolve it. Runs entirely in your browser. It runs free in your browser on Gera Tools, with nothing uploaded.

Twilio Error Codes Reference

Name: Twilio Error Codes Reference
Creator: Gera Tools
License: https://creativecommons.org/licenses/by/4.0/

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This is a searchable reference for Twilio error and warning codes across the products you actually integrate — the REST API, Programmable Messaging (SMS/MMS), Programmable Voice, Verify, and Video. Each entry shows the product area that raised the code, what it means, and how to resolve it, so you can tell a request mistake from a delivery failure at a glance.

How Twilio organises error codes

Twilio assigns error codes into numeric ranges that map to a product and to a point in the lifecycle:

1xxxx   Voice / TwiML retrieval and execution (e.g. 11200 HTTP retrieval failure)
21xxx   REST API request errors — synchronous, returned on the API call
30xxx   Messaging delivery errors — asynchronous, via status callbacks
53xxx   Video room and participant errors
60xxx   Verify / Authy (e.g. 60200 invalid parameter)

The most important distinction is synchronous vs asynchronous:

Synchronous (21xxx): Returned immediately with a non-2xx HTTP status and a code field in the response body. These mean the API call itself was rejected — bad To number, missing parameter, unverified caller ID, or trial account restriction.
Asynchronous (30xxx): Arrive later in a MessageStatus webhook callback. The API call returned 201 Created, but the carrier later rejected or could not deliver the message. If you are not wiring up a status callback URL, these errors are invisible.

The errors you will encounter most often

Code	Product	Meaning	Fix
21211	Messaging	Invalid `To` phone number	Use E.164 format: `+14155551234`
21608	Messaging	Trial account, unverified recipient	Verify the number in console
11200	Voice	HTTP retrieval failure (TwiML fetch failed)	Make webhook public, return valid TwiML, check TLS
30003	Messaging	Unreachable destination handset	Phone off or out of coverage; retry later
30007	Messaging	Message blocked by carrier	Register A2P 10DLC brand + campaign
30034	Messaging	Message blocked — unregistered sender	Complete 10DLC registration with TCR
60200	Verify	Invalid parameter	Check the `to` number and channel parameter

Why 30007 and 30034 are so common

Since US carriers began enforcing A2P 10DLC registration, unregistered application-to-person SMS traffic is routinely filtered. 30007 (carrier filtering) and 30034 (unregistered sender) now account for a large share of delivery failures. The fix is registering your brand and campaign with The Campaign Registry (TCR) and linking them to the Twilio messaging service you use to send. Once registered, most filtering clears within 24 to 48 hours.

Tips for debugging

Always wire up a StatusCallback URL on your messaging requests so 30xxx errors surface in your logs rather than silently disappearing.
A 201 Created from the Twilio REST API only confirms Twilio accepted the request — it says nothing about carrier delivery.
For Voice, 11200 almost always means your TwiML webhook returned something that is not a 200 OK with a valid XML body, or the URL is blocked by a firewall or basic auth.
Use the search field here to filter by code number, product area, or keyword so you do not have to scroll the full list. Everything runs in your browser; nothing is uploaded.