# Elevated 5xx Transmissions API error rates and latency for some SparkPost customers (US hosted only)

- Provider: [SparkPost](https://down.guide/providers/sparkpost)
- Confidence: Confirmed
- Impact: Partial outage
- lasted 34m
- started 2026-02-24 19:07 UTC
- Transmissions API - USA
- eu, us
- id: DWN-fa2edf189e
- Official page: https://stspg.io/vdhpx4p0k53n

## Updates from SparkPost
### 2026-02-24 19:07 UTC: investigating
We are experiencing an elevated level of errors and latency on the Transmissions API (injection API) for some SparkPost customers. Please retry any 5xx error.
Note: This issue does not impact SparkPost customers hosted in the EU.

### 2026-02-24 19:07 UTC: investigating
We are continuing to investigate this issue.

### 2026-02-24 19:25 UTC: investigating
We are continuing to investigate this issue. We still see 5xx errors on mail injections and degradation.

### 2026-02-24 19:34 UTC: identified
The team has identified the root cause. There is a core networking issue that has impacted sending across the clusters.

### 2026-02-24 19:38 UTC: monitoring
A fix has been implemented and we are monitoring the results.

### 2026-02-24 19:41 UTC: resolved
This incident has been resolved.

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