Alerting: the legacy Alertmanager UI is no longer available in Grafana Cloud

The legacy Prometheus Alertmanager built-in UI is no longer available in Grafana Cloud. This is the old Alertmanager web interface, served per cluster at alertmanager-<cluster>.grafana.net and reached through a separate OAuth login (its URLs contain a /#/ fragment, for example /#/alerts).

This change affects only the web interface. The Alertmanager API is unchanged.

Grafana deprecated this UI several years ago in favor of its native alerting experience, and access has been progressively turned off over that time. This change is expected to affect a small number of users.

If you were still relying on the old Alertmanager UI and need help, reach out to Customer Support and we’ll work with you on the best alternative for your use case.

2026-06-08

Alerting: contact point logic update

2026-05-06

Alerting: Grafana-Managed Alerting is the default in new stacks

2026-04-22

Anomaly Alerts (Usage Spike Detection)