SMS Delivery Receipt Delays from a Subset of Twilio International Pre-Registered Sender IDs to Vinaphone Vietnam

Incident Report for Twilio

Resolved

The incident has been resolved and SMS delivery receipts from a subset of Twilio International Pre-Registered Sender IDs to Vinaphone network subscribers in Vietnam are operating normally.
Posted Aug 22, 2026 - 00:07 PDT

Monitoring

We have observed a recovery in SMS delivery receipts from a subset of Twilio International Pre-Registered Sender IDs to Vinaphone network subscribers in Vietnam and are monitoring service stability. We will provide another update in 2 hours or as soon as more information becomes available.
Posted Aug 21, 2026 - 22:06 PDT

Update

Twilio customers may be experiencing SMS delivery receipt delays from a subset of Twilio International Pre-Registered Sender IDs to Vinaphone network subscribers in Vietnam. Our team has identified the cause, and is working to resolve the issue. Message delivery may succeed, but delivery receipts may be delayed. We will provide another update in 2 hours or as soon as more information becomes available.
Posted Aug 21, 2026 - 21:46 PDT

Identified

Twilio customers may be experiencing SMS delivery receipt delays from a subset of Twilio International Pre-Registered Sender IDs to Vinaphone network subscribers in Vietnam. Our team has identified the cause, and is working to resolve the issue. Message delivery may succeed, but delivery receipts may be delayed. We will provide another update in 1 hour or as soon as more information becomes available.
Posted Aug 21, 2026 - 20:45 PDT

Investigating

Twilio customers may be experiencing SMS delivery receipt delays from a subset of Twilio International Pre-Registered Sender IDs to Vinaphone network subscribers in Vietnam. Our team is actively investigating this issue. Message delivery may succeed, but delivery receipts may be delayed. We will provide another update in 1 hour or as soon as more information becomes available.
Posted Aug 21, 2026 - 20:43 PDT
This incident affected: CARRIER NETWORK (SMS, APAC).