diff --git a/CHANGES.md b/CHANGES.md
index 666a6c74..2cbe586d 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -17,6 +17,7 @@ Notable changes between versions.
 ### Addons
 
 * Update IngressClass resources to `networking.k8s.io/v1` ([#824](https://github.com/poseidon/typhoon/pull/824))
+* Update Prometheus from v2.20.0 to [v2.21.0](https://github.com/prometheus/prometheus/releases/tag/v2.21.0)
 
 ## v1.19.0
 
diff --git a/addons/prometheus/deployment.yaml b/addons/prometheus/deployment.yaml
index 5ffd82fc..a2d5a7a9 100644
--- a/addons/prometheus/deployment.yaml
+++ b/addons/prometheus/deployment.yaml
@@ -21,7 +21,7 @@ spec:
       serviceAccountName: prometheus
       containers:
         - name: prometheus
-          image: quay.io/prometheus/prometheus:v2.20.0
+          image: quay.io/prometheus/prometheus:v2.21.0
           args:
             - --web.listen-address=0.0.0.0:9090
             - --config.file=/etc/prometheus/prometheus.yaml