diff --git a/README.md b/README.md
index 0ffba67..afadcba 100644
--- a/README.md
+++ b/README.md
@@ -639,7 +639,9 @@ Chart configuration is as follows:
 | `nodeSelector` | `{}` | Standard Kubernetes stuff |
 | `tolerations` | `[]` | Standard Kubernetes stuff |
 | `affinity` | `{}` | Standard Kubernetes stuff |
-| `certs.create` | `{}` | Auto generate TLS certificates for Postfix |
+| `certs.create` | `false` | Auto generate TLS certificates for Postfix |
+| `certs.existing` | `false` | Use existing TLS certificates for Postfix |
+| `certs.existingSecret` | `""` | Existing secret containing the TLS certificates for Postfix |
 | `extraVolumes` | `[]` | Append any extra volumes to the pod |
 | `extraVolumeMounts` | `[]` | Append any extra volume mounts to the postfix container |
 | `extraInitContainers` | `[]` | Execute any extra init containers on startup |
diff --git a/helm/mail/templates/_helpers.tpl b/helm/mail/templates/_helpers.tpl
index 1eef90a..8ec6fdb 100644
--- a/helm/mail/templates/_helpers.tpl
+++ b/helm/mail/templates/_helpers.tpl
@@ -84,6 +84,6 @@ Return the secret containing HTTPS/TLS certificates
 {{- if $secretName -}}
     {{- printf "%s" (tpl $secretName .) -}}
 {{- else -}}
-    {{- printf "smtp-relay-mail-certs" -}}
+    {{- printf "%s-certs" (include "mail.fullname" .) -}}
 {{- end -}}
 {{- end -}}
diff --git a/helm/test_16_test_existing_certs.yml b/helm/test_16_test_existing_certs.yml
new file mode 100644
index 0000000..844fd8b
--- /dev/null
+++ b/helm/test_16_test_existing_certs.yml
@@ -0,0 +1,3 @@
+certs:
+  existing: true
+  existingSecret: "example-tls"
\ No newline at end of file