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A2PCheck

Twilio Error 30001: Queue Overflow

Error 30001 is queue overflow: you queued messages faster than your sender can send them, and the backlog exceeded what Twilio will hold.

Guidance only — A2PCheck is independent and not affiliated with Twilio, The Campaign Registry, or any carrier, and we can't guarantee approval.

What Twilio error 30001 means

Your outbound queue exceeded capacity. Twilio queues messages according to the sending rate of the sender or account, and messages can only sit in the queue for up to a limited window before they automatically fail.

Official Twilio name: 30001: Queue Overflow

Why error 30001 happens

You sent faster than your sender's throughput allows — a single long code sends roughly one message per second, so a burst of thousands from one number backs up immediately. Hitting the MPS limit on a sender, Messaging Service, or account causes the queue to overflow.

How to fix error 30001

  1. Send through a Messaging Service with multiple senders so Twilio can load-balance across numbers.
  2. Add more senders to the Messaging Service to raise aggregate throughput.
  3. For high volume in the US/Canada, use toll-free or short-code senders, which support higher MPS.
  4. Pace your sends and increase the Validity Period so messages aren't dropped as quickly while queued.
  5. Watch queue depth via Queue Insights to catch overflow before it fails messages.

Related error codes

Twilio error 30022: US A2P 10DLC - Rate Limits ExceededThroughput & daily capsTwilio error 30023: US A2P 10DLC - Daily Message Cap ReachedThroughput & daily caps

Official reference

For the authoritative definition and any changes to this code, see the Twilioerror catalog. A2PCheck is an independent pre-scan layer for the campaign packet you submit — it can't change carrier behavior.

Twilio error 30001 documentation

Frequently asked questions

Is 30001 the same as the A2P throughput error 30022?

No. 30001 is Twilio's own outbound queue overflowing because you're sending faster than your sender's MPS. 30022 is a downstream carrier rejecting A2P 10DLC traffic for exceeding your registered campaign's throughput. Both are rate problems, but at different layers.

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Many of these errors trace back to an unregistered, mis-scoped, or non-compliant A2P 10DLC campaign. Paste your campaign details for a free readiness scan — no signup.

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01

Campaign Info

Basic details about your messaging campaign.

0 characters — Too short — describe who opts in, what you send, and how often.

02

Sample Messages

Provide at least 2 example messages you'll send.

STOP foundHELP foundchecked across your keywords & messages
03

Opt-In / Message Flow

How users consent to receive your messages.

Consent evidence readiness

Describe where and how subscribers consent — name the opt-in location and the consent language they agree to.

  • Name the opt-in location (web form, checkout, keyword, QR code, paper form, etc.).
  • Spell out the consent language — what the subscriber explicitly agrees to.
  • State the message frequency (e.g. recurring, varies, msgs/month).
  • Include a "Message and data rates may apply" disclosure.
  • Link a privacy policy describing how you handle subscriber data.
  • Clarify that consent isn't a condition of purchase, where that applies.
  • Capture and retain opt-in evidence (timestamp, source URL, exact consent text/screenshot) for each subscriber.

Guidance only — consent requirements can vary by use case and jurisdiction.

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