diff --git a/traefik/templates/prometheusrules.yaml b/traefik/templates/prometheusrules.yaml
index fa786051b..4534964d1 100644
--- a/traefik/templates/prometheusrules.yaml
+++ b/traefik/templates/prometheusrules.yaml
@@ -9,9 +9,7 @@ apiVersion: monitoring.coreos.com/v1
 kind: PrometheusRule
 metadata:
   name: {{ template "traefik.fullname" . }}
-  {{- if .Values.metrics.prometheus.prometheusRule.namespace }}
-  namespace: {{ .Values.metrics.prometheus.prometheusRule.namespace }}
-  {{- end }}
+  namespace: {{ .Values.metrics.prometheus.prometheusRule.namespace | default (include "traefik.namespace" .) }}
   labels:
     {{- include "traefik.labels" . | nindent 4 }}
     {{- with .Values.metrics.prometheus.prometheusRule.additionalLabels }}
diff --git a/traefik/templates/servicemonitor.yaml b/traefik/templates/servicemonitor.yaml
index f3e128405..a4a8eda92 100644
--- a/traefik/templates/servicemonitor.yaml
+++ b/traefik/templates/servicemonitor.yaml
@@ -9,9 +9,7 @@ apiVersion: monitoring.coreos.com/v1
 kind: ServiceMonitor
 metadata:
   name: {{ template "traefik.fullname" . }}
-  {{- with .Values.metrics.prometheus.serviceMonitor.namespace }}
-  namespace: {{ . }}
-  {{- end }}
+  namespace: {{ .Values.metrics.prometheus.serviceMonitor.namespace | default (include "traefik.namespace" .) }}
   labels:
     {{- if (.Values.metrics.prometheus.service).enabled }}
     {{- include "traefik.metricsservicelabels" . | nindent 4 }}
diff --git a/traefik/tests/prometheusrules-config_test.yaml b/traefik/tests/prometheusrules-config_test.yaml
index 50399cc46..09d3dc4a0 100644
--- a/traefik/tests/prometheusrules-config_test.yaml
+++ b/traefik/tests/prometheusrules-config_test.yaml
@@ -51,3 +51,36 @@ tests:
                 labels:
                   context: traefik
                   severity: warning
+  - it: should use the release namespace by default if metrics.prometheus.prometheusRule.namespace is not set
+    capabilities:
+      apiVersions:
+        - monitoring.coreos.com/v1
+    values:
+      - ./values/prometheusrules.yaml
+    release:
+      namespace: release-namespace
+    set:
+      metrics:
+        prometheus:
+          prometheusRule:
+            namespace: ""
+    asserts:
+      - hasDocuments:
+          count: 1
+      - equal:
+          path: metadata.namespace
+          value: release-namespace
+  - it: should use the release namespace if specified
+    capabilities:
+      apiVersions:
+        - monitoring.coreos.com/v1
+    values:
+      - ./values/prometheusrules.yaml
+    release:
+      namespace: release-namespace
+    asserts:
+      - hasDocuments:
+          count: 1
+      - equal:
+          path: metadata.namespace
+          value: another-namespace
diff --git a/traefik/tests/servicemonitor-config_test.yaml b/traefik/tests/servicemonitor-config_test.yaml
index 20f640ecc..210fc3776 100644
--- a/traefik/tests/servicemonitor-config_test.yaml
+++ b/traefik/tests/servicemonitor-config_test.yaml
@@ -83,3 +83,36 @@ tests:
       - equal:
           path: spec.selector.matchLabels["app.kubernetes.io/component"]
           value: metrics
+  - it: should use the release namespace by default if metrics.prometheus.serviceMonitor.namespace is not set
+    capabilities:
+      apiVersions:
+        - monitoring.coreos.com/v1
+    values:
+      - ./values/servicemonitor.yaml
+    release:
+      namespace: release-namespace
+    set:
+      metrics:
+        prometheus:
+          serviceMonitor:
+            namespace: ""
+    asserts:
+      - hasDocuments:
+          count: 1
+      - equal:
+          path: metadata.namespace
+          value: release-namespace
+  - it: should use the release namespace if specified
+    capabilities:
+      apiVersions:
+        - monitoring.coreos.com/v1
+    values:
+      - ./values/servicemonitor.yaml
+    release:
+      namespace: release-namespace
+    asserts:
+      - hasDocuments:
+          count: 1
+      - equal:
+          path: metadata.namespace
+          value: another-namespace