Twilio Error 30450: Message Delivery Blocked (SMS Pumping)

Error 30450 is a temporary fraud block: SMS Pumping Protection flagged the request as suspicious and held delivery to reduce SMS pumping fraud.

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 30450 means

Twilio blocked delivery to the destination number because SMS Pumping Protection identified the request as suspicious. The block is temporary and exists to reduce SMS pumping fraud.

Official Twilio name: 30450: Message Delivery Blocked

Why error 30450 happens

Unusual traffic patterns for the destination number or region, a destination matching known malicious patterns, or high-volume OTP/verification sends triggered the protection. It's most common on authentication traffic that suddenly spikes to specific number ranges.

How to fix error 30450

Wait 15-30 minutes for the temporary block to expire, then retry.
Review your traffic for unusual high-volume OTP or verification bursts to specific regions.
Keep RiskCheck enabled for authentication traffic so genuine fraud is caught.
For confirmed-legitimate flows, set RiskCheck to disable, or add known-good numbers to the Global Safe List.
If legitimate traffic keeps getting blocked, contact Support with three recent Message SIDs.

Related error codes

Twilio error 30007: Message FilteredCarrier filtering & content blocks Twilio error 30004: Message BlockedCarrier filtering & content blocks Twilio error 30002: Account SuspendedAccount, billing & fraud protection

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 30450 documentation

Frequently asked questions

Is error 30450 permanent?

No. 30450 is a temporary block from SMS Pumping Protection — typically 15-30 minutes — meant to curb SMS pumping fraud. Retry after it expires, and for legitimate high-volume flows use the Global Safe List or adjust RiskCheck.

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