Twilio incident
Voice Call Audio Quality Degradation between a Subset of Twilio United States Phone Numbers and T-Mobile in United States
Resolved after 2 days 5 hours, affecting Voice, North America, on May 11, 2026.
The incident has been resolved and voice calls between a subset of Twilio United States Phone Numbers and T-Mobile network subscribers in the United States are operating normally.
Affected components
Update timeline
- investigating May 11, 2026, 04:04 PM UTC
Twilio customers may be experiencing voice call audio quality degradation between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States. Our team is actively investigating this issue. We will provide another update in 1 hour or as soon as more information becomes available.
- identified May 11, 2026, 04:27 PM UTC
Twilio customers may be experiencing voice call audio quality degradation between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States. Our team has identified the cause, and is working to resolve the issue. We will provide another update in 1 hour or as soon as more information becomes available.
- identified May 11, 2026, 05:30 PM UTC
Twilio customers may be experiencing voice call audio quality degradation between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States. Our team has identified the cause, and is working to resolve the issue. We will provide another update in 2 hours or as soon as more information becomes available.
- identified May 11, 2026, 07:31 PM UTC
Twilio customers may be experiencing voice call audio quality degradation between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States. Our team has identified the cause, and is working to resolve the issue. We will provide another update in 4 hours or as soon as more information becomes available.
- identified May 11, 2026, 11:31 PM UTC
Twilio customers may be experiencing voice call audio quality degradation between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States. Our team has identified the cause, and is working to resolve the issue. We will provide another update in 8 hours or as soon as more information becomes available.
- monitoring May 11, 2026, 11:43 PM UTC
We have observed a recovery in voice calls between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 2 hours or as soon as more information becomes available.
- monitoring May 12, 2026, 01:49 AM UTC
We have observed a recovery in voice calls between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 4 hours or as soon as more information becomes available.
- monitoring May 12, 2026, 05:55 AM UTC
We have observed a recovery in voice calls between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 8 hours or as soon as more information becomes available.
- monitoring May 12, 2026, 01:55 PM UTC
We have observed a recovery in voice calls between a subset of Twilio United States Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 16 hours or as soon as more information becomes available.
- identified May 12, 2026, 03:58 PM UTC
Twilio customers may be experiencing voice call audio quality degradation between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States. Our team has identified the cause, and is working to resolve the issue. We will provide another update in 1 hour or as soon as more information becomes available.
- monitoring May 12, 2026, 04:58 PM UTC
We have observed a recovery in voice calls between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 2 hours or as soon as more information becomes available.
- monitoring May 12, 2026, 06:59 PM UTC
We have observed a recovery in voice calls between a subset of Twilio United States Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 4 hours or as soon as more information becomes available.
- monitoring May 12, 2026, 11:00 PM UTC
We have observed a recovery in voice calls between a subset of Twilio United States Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 8 hours or as soon as more information becomes available.
- monitoring May 13, 2026, 07:00 AM UTC
We have observed a recovery in voice calls between a subset of Twilio United States Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 16 hours or as soon as more information becomes available.
- resolved May 13, 2026, 09:11 PM UTC
The incident has been resolved and voice calls between a subset of Twilio United States Phone Numbers and T-Mobile network subscribers in the United States are operating normally.
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