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

Incident Report for SparkPost

Resolved

This incident has been resolved.
Posted May 11, 2026 - 16:02 EDT

Monitoring

A fix has been implemented and we are monitoring the results.
Posted May 11, 2026 - 15:46 EDT

Identified

We are experiencing an elevated level of errors and latency on the Suppression List API for some SparkPost customers. Please retry any 5xx error.

Note: This issue does not impact SparkPost customers hosted in the EU.
Posted May 11, 2026 - 14:55 EDT
This incident affected: Suppression List API (Suppression List API - USA).