# SendGrid: Voice Call Failures from a Subset of Twilio Phone Numbers to T-Mobile United States

- Provider: [SendGrid](https://outages.cc/sendgrid.md)
- Type: Incident
- State: Resolved
- Worst impact: Degraded performance
- Started: 2026-10-29 01:34 UTC
- Resolved: 2026-10-29 14:20 UTC (lasted 12 h 46 min)
- Components: Voice, North America, CARRIER NETWORK - Voice, North America
- Official update: https://stspg.io/h222bhk6xb0k

## Updates from SendGrid

### resolved, 2026-10-29 14:20 UTC

The incident has been resolved and voice calls from a subset of Twilio Phone Numbers to T-Mobile network subscribers in the United States are operating normally.

### monitoring, 2026-10-29 11:55 UTC

We have observed a recovery in voice calls from a subset of Twilio Phone Numbers to 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, 2026-10-29 07:55 UTC

We have observed a recovery in voice calls from a subset of Twilio Phone Numbers to 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, 2026-10-29 05:54 UTC

We have observed a recovery in voice calls from a subset of Twilio Phone Numbers to 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.

### identified, 2026-10-29 04:01 UTC

Twilio customers may be experiencing voice call failures from a subset of Twilio Phone Numbers to 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, 2026-10-29 02:58 UTC

Twilio customers may be experiencing voice call failures from a subset of Twilio Phone Numbers to 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, 2026-10-29 01:45 UTC

We have observed a recovery in voice calls from a subset of Twilio Phone Numbers to 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.

### identified, 2026-10-29 01:43 UTC

Twilio customers may be experiencing voice call failures from a subset of Twilio Phone Numbers to 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.

### investigating, 2026-10-29 01:34 UTC

Twilio customers may be experiencing voice call failures from a subset of Twilio Phone Numbers to 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.