diff --git a/.config/smtp.config.php b/.config/smtp.config.php
index 59f1eaa1..62880e4b 100644
--- a/.config/smtp.config.php
+++ b/.config/smtp.config.php
@@ -8,8 +8,15 @@ if (getenv('SMTP_HOST') && getenv('MAIL_FROM_ADDRESS') && getenv('MAIL_DOMAIN'))
     'mail_smtpauth' => getenv('SMTP_NAME') && getenv('SMTP_PASSWORD'),
     'mail_smtpauthtype' => getenv('SMTP_AUTHTYPE') ?: 'LOGIN',
     'mail_smtpname' => getenv('SMTP_NAME') ?: '',
-    'mail_smtppassword' => getenv('SMTP_PASSWORD') ?: '',
     'mail_from_address' => getenv('MAIL_FROM_ADDRESS'),
     'mail_domain' => getenv('MAIL_DOMAIN'),
   );
+
+  if (getenv('SMTP_PASSWORD_FILE') && file_exists(getenv('SMTP_PASSWORD_FILE'))) {
+      $CONFIG['mail_smtppassword'] = trim(file_get_contents(getenv('SMTP_PASSWORD_FILE')));
+  } elseif (getenv('SMTP_PASSWORD')) {
+      $CONFIG['mail_smtppassword'] = getenv('SMTP_PASSWORD');
+  } else {
+      $CONFIG['mail_smtppassword'] = '';
+  }
 }
diff --git a/20.0/apache/config/smtp.config.php b/20.0/apache/config/smtp.config.php
index 59f1eaa1..62880e4b 100644
--- a/20.0/apache/config/smtp.config.php
+++ b/20.0/apache/config/smtp.config.php
@@ -8,8 +8,15 @@ if (getenv('SMTP_HOST') && getenv('MAIL_FROM_ADDRESS') && getenv('MAIL_DOMAIN'))
     'mail_smtpauth' => getenv('SMTP_NAME') && getenv('SMTP_PASSWORD'),
     'mail_smtpauthtype' => getenv('SMTP_AUTHTYPE') ?: 'LOGIN',
     'mail_smtpname' => getenv('SMTP_NAME') ?: '',
-    'mail_smtppassword' => getenv('SMTP_PASSWORD') ?: '',
     'mail_from_address' => getenv('MAIL_FROM_ADDRESS'),
     'mail_domain' => getenv('MAIL_DOMAIN'),
   );
+
+  if (getenv('SMTP_PASSWORD_FILE') && file_exists(getenv('SMTP_PASSWORD_FILE'))) {
+      $CONFIG['mail_smtppassword'] = trim(file_get_contents(getenv('SMTP_PASSWORD_FILE')));
+  } elseif (getenv('SMTP_PASSWORD')) {
+      $CONFIG['mail_smtppassword'] = getenv('SMTP_PASSWORD');
+  } else {
+      $CONFIG['mail_smtppassword'] = '';
+  }
 }
diff --git a/20.0/fpm-alpine/config/smtp.config.php b/20.0/fpm-alpine/config/smtp.config.php
index 59f1eaa1..62880e4b 100644
--- a/20.0/fpm-alpine/config/smtp.config.php
+++ b/20.0/fpm-alpine/config/smtp.config.php
@@ -8,8 +8,15 @@ if (getenv('SMTP_HOST') && getenv('MAIL_FROM_ADDRESS') && getenv('MAIL_DOMAIN'))
     'mail_smtpauth' => getenv('SMTP_NAME') && getenv('SMTP_PASSWORD'),
     'mail_smtpauthtype' => getenv('SMTP_AUTHTYPE') ?: 'LOGIN',
     'mail_smtpname' => getenv('SMTP_NAME') ?: '',
-    'mail_smtppassword' => getenv('SMTP_PASSWORD') ?: '',
     'mail_from_address' => getenv('MAIL_FROM_ADDRESS'),
     'mail_domain' => getenv('MAIL_DOMAIN'),
   );
+
+  if (getenv('SMTP_PASSWORD_FILE') && file_exists(getenv('SMTP_PASSWORD_FILE'))) {
+      $CONFIG['mail_smtppassword'] = trim(file_get_contents(getenv('SMTP_PASSWORD_FILE')));
+  } elseif (getenv('SMTP_PASSWORD')) {
+      $CONFIG['mail_smtppassword'] = getenv('SMTP_PASSWORD');
+  } else {
+      $CONFIG['mail_smtppassword'] = '';
+  }
 }
diff --git a/20.0/fpm/config/smtp.config.php b/20.0/fpm/config/smtp.config.php
index 59f1eaa1..62880e4b 100644
--- a/20.0/fpm/config/smtp.config.php
+++ b/20.0/fpm/config/smtp.config.php
@@ -8,8 +8,15 @@ if (getenv('SMTP_HOST') && getenv('MAIL_FROM_ADDRESS') && getenv('MAIL_DOMAIN'))
     'mail_smtpauth' => getenv('SMTP_NAME') && getenv('SMTP_PASSWORD'),
     'mail_smtpauthtype' => getenv('SMTP_AUTHTYPE') ?: 'LOGIN',
     'mail_smtpname' => getenv('SMTP_NAME') ?: '',
-    'mail_smtppassword' => getenv('SMTP_PASSWORD') ?: '',
     'mail_from_address' => getenv('MAIL_FROM_ADDRESS'),
     'mail_domain' => getenv('MAIL_DOMAIN'),
   );
+
+  if (getenv('SMTP_PASSWORD_FILE') && file_exists(getenv('SMTP_PASSWORD_FILE'))) {
+      $CONFIG['mail_smtppassword'] = trim(file_get_contents(getenv('SMTP_PASSWORD_FILE')));
+  } elseif (getenv('SMTP_PASSWORD')) {
+      $CONFIG['mail_smtppassword'] = getenv('SMTP_PASSWORD');
+  } else {
+      $CONFIG['mail_smtppassword'] = '';
+  }
 }
diff --git a/21.0/apache/config/smtp.config.php b/21.0/apache/config/smtp.config.php
index 59f1eaa1..62880e4b 100644
--- a/21.0/apache/config/smtp.config.php
+++ b/21.0/apache/config/smtp.config.php
@@ -8,8 +8,15 @@ if (getenv('SMTP_HOST') && getenv('MAIL_FROM_ADDRESS') && getenv('MAIL_DOMAIN'))
     'mail_smtpauth' => getenv('SMTP_NAME') && getenv('SMTP_PASSWORD'),
     'mail_smtpauthtype' => getenv('SMTP_AUTHTYPE') ?: 'LOGIN',
     'mail_smtpname' => getenv('SMTP_NAME') ?: '',
-    'mail_smtppassword' => getenv('SMTP_PASSWORD') ?: '',
     'mail_from_address' => getenv('MAIL_FROM_ADDRESS'),
     'mail_domain' => getenv('MAIL_DOMAIN'),
   );
+
+  if (getenv('SMTP_PASSWORD_FILE') && file_exists(getenv('SMTP_PASSWORD_FILE'))) {
+      $CONFIG['mail_smtppassword'] = trim(file_get_contents(getenv('SMTP_PASSWORD_FILE')));
+  } elseif (getenv('SMTP_PASSWORD')) {
+      $CONFIG['mail_smtppassword'] = getenv('SMTP_PASSWORD');
+  } else {
+      $CONFIG['mail_smtppassword'] = '';
+  }
 }
diff --git a/21.0/fpm-alpine/config/smtp.config.php b/21.0/fpm-alpine/config/smtp.config.php
index 59f1eaa1..62880e4b 100644
--- a/21.0/fpm-alpine/config/smtp.config.php
+++ b/21.0/fpm-alpine/config/smtp.config.php
@@ -8,8 +8,15 @@ if (getenv('SMTP_HOST') && getenv('MAIL_FROM_ADDRESS') && getenv('MAIL_DOMAIN'))
     'mail_smtpauth' => getenv('SMTP_NAME') && getenv('SMTP_PASSWORD'),
     'mail_smtpauthtype' => getenv('SMTP_AUTHTYPE') ?: 'LOGIN',
     'mail_smtpname' => getenv('SMTP_NAME') ?: '',
-    'mail_smtppassword' => getenv('SMTP_PASSWORD') ?: '',
     'mail_from_address' => getenv('MAIL_FROM_ADDRESS'),
     'mail_domain' => getenv('MAIL_DOMAIN'),
   );
+
+  if (getenv('SMTP_PASSWORD_FILE') && file_exists(getenv('SMTP_PASSWORD_FILE'))) {
+      $CONFIG['mail_smtppassword'] = trim(file_get_contents(getenv('SMTP_PASSWORD_FILE')));
+  } elseif (getenv('SMTP_PASSWORD')) {
+      $CONFIG['mail_smtppassword'] = getenv('SMTP_PASSWORD');
+  } else {
+      $CONFIG['mail_smtppassword'] = '';
+  }
 }
diff --git a/21.0/fpm/config/smtp.config.php b/21.0/fpm/config/smtp.config.php
index 59f1eaa1..62880e4b 100644
--- a/21.0/fpm/config/smtp.config.php
+++ b/21.0/fpm/config/smtp.config.php
@@ -8,8 +8,15 @@ if (getenv('SMTP_HOST') && getenv('MAIL_FROM_ADDRESS') && getenv('MAIL_DOMAIN'))
     'mail_smtpauth' => getenv('SMTP_NAME') && getenv('SMTP_PASSWORD'),
     'mail_smtpauthtype' => getenv('SMTP_AUTHTYPE') ?: 'LOGIN',
     'mail_smtpname' => getenv('SMTP_NAME') ?: '',
-    'mail_smtppassword' => getenv('SMTP_PASSWORD') ?: '',
     'mail_from_address' => getenv('MAIL_FROM_ADDRESS'),
     'mail_domain' => getenv('MAIL_DOMAIN'),
   );
+
+  if (getenv('SMTP_PASSWORD_FILE') && file_exists(getenv('SMTP_PASSWORD_FILE'))) {
+      $CONFIG['mail_smtppassword'] = trim(file_get_contents(getenv('SMTP_PASSWORD_FILE')));
+  } elseif (getenv('SMTP_PASSWORD')) {
+      $CONFIG['mail_smtppassword'] = getenv('SMTP_PASSWORD');
+  } else {
+      $CONFIG['mail_smtppassword'] = '';
+  }
 }
diff --git a/22.0/apache/config/smtp.config.php b/22.0/apache/config/smtp.config.php
index 59f1eaa1..62880e4b 100644
--- a/22.0/apache/config/smtp.config.php
+++ b/22.0/apache/config/smtp.config.php
@@ -8,8 +8,15 @@ if (getenv('SMTP_HOST') && getenv('MAIL_FROM_ADDRESS') && getenv('MAIL_DOMAIN'))
     'mail_smtpauth' => getenv('SMTP_NAME') && getenv('SMTP_PASSWORD'),
     'mail_smtpauthtype' => getenv('SMTP_AUTHTYPE') ?: 'LOGIN',
     'mail_smtpname' => getenv('SMTP_NAME') ?: '',
-    'mail_smtppassword' => getenv('SMTP_PASSWORD') ?: '',
     'mail_from_address' => getenv('MAIL_FROM_ADDRESS'),
     'mail_domain' => getenv('MAIL_DOMAIN'),
   );
+
+  if (getenv('SMTP_PASSWORD_FILE') && file_exists(getenv('SMTP_PASSWORD_FILE'))) {
+      $CONFIG['mail_smtppassword'] = trim(file_get_contents(getenv('SMTP_PASSWORD_FILE')));
+  } elseif (getenv('SMTP_PASSWORD')) {
+      $CONFIG['mail_smtppassword'] = getenv('SMTP_PASSWORD');
+  } else {
+      $CONFIG['mail_smtppassword'] = '';
+  }
 }
diff --git a/22.0/fpm-alpine/config/smtp.config.php b/22.0/fpm-alpine/config/smtp.config.php
index 59f1eaa1..62880e4b 100644
--- a/22.0/fpm-alpine/config/smtp.config.php
+++ b/22.0/fpm-alpine/config/smtp.config.php
@@ -8,8 +8,15 @@ if (getenv('SMTP_HOST') && getenv('MAIL_FROM_ADDRESS') && getenv('MAIL_DOMAIN'))
     'mail_smtpauth' => getenv('SMTP_NAME') && getenv('SMTP_PASSWORD'),
     'mail_smtpauthtype' => getenv('SMTP_AUTHTYPE') ?: 'LOGIN',
     'mail_smtpname' => getenv('SMTP_NAME') ?: '',
-    'mail_smtppassword' => getenv('SMTP_PASSWORD') ?: '',
     'mail_from_address' => getenv('MAIL_FROM_ADDRESS'),
     'mail_domain' => getenv('MAIL_DOMAIN'),
   );
+
+  if (getenv('SMTP_PASSWORD_FILE') && file_exists(getenv('SMTP_PASSWORD_FILE'))) {
+      $CONFIG['mail_smtppassword'] = trim(file_get_contents(getenv('SMTP_PASSWORD_FILE')));
+  } elseif (getenv('SMTP_PASSWORD')) {
+      $CONFIG['mail_smtppassword'] = getenv('SMTP_PASSWORD');
+  } else {
+      $CONFIG['mail_smtppassword'] = '';
+  }
 }
diff --git a/22.0/fpm/config/smtp.config.php b/22.0/fpm/config/smtp.config.php
index 59f1eaa1..62880e4b 100644
--- a/22.0/fpm/config/smtp.config.php
+++ b/22.0/fpm/config/smtp.config.php
@@ -8,8 +8,15 @@ if (getenv('SMTP_HOST') && getenv('MAIL_FROM_ADDRESS') && getenv('MAIL_DOMAIN'))
     'mail_smtpauth' => getenv('SMTP_NAME') && getenv('SMTP_PASSWORD'),
     'mail_smtpauthtype' => getenv('SMTP_AUTHTYPE') ?: 'LOGIN',
     'mail_smtpname' => getenv('SMTP_NAME') ?: '',
-    'mail_smtppassword' => getenv('SMTP_PASSWORD') ?: '',
     'mail_from_address' => getenv('MAIL_FROM_ADDRESS'),
     'mail_domain' => getenv('MAIL_DOMAIN'),
   );
+
+  if (getenv('SMTP_PASSWORD_FILE') && file_exists(getenv('SMTP_PASSWORD_FILE'))) {
+      $CONFIG['mail_smtppassword'] = trim(file_get_contents(getenv('SMTP_PASSWORD_FILE')));
+  } elseif (getenv('SMTP_PASSWORD')) {
+      $CONFIG['mail_smtppassword'] = getenv('SMTP_PASSWORD');
+  } else {
+      $CONFIG['mail_smtppassword'] = '';
+  }
 }
diff --git a/README.md b/README.md
index 53a1c2bb..f0501730 100644
--- a/README.md
+++ b/README.md
@@ -373,7 +373,7 @@ secrets:
     file: ./postgres_user.txt # put postgresql username to this file
 ```
 
-Currently, this is only supported for `NEXTCLOUD_ADMIN_PASSWORD`, `NEXTCLOUD_ADMIN_USER`, `MYSQL_DATABASE`, `MYSQL_PASSWORD`, `MYSQL_USER`, `POSTGRES_DB`, `POSTGRES_PASSWORD`, `POSTGRES_USER` and `REDIS_HOST_PASSWORD`.
+Currently, this is only supported for `NEXTCLOUD_ADMIN_PASSWORD`, `NEXTCLOUD_ADMIN_USER`, `MYSQL_DATABASE`, `MYSQL_PASSWORD`, `MYSQL_USER`, `POSTGRES_DB`, `POSTGRES_PASSWORD`, `POSTGRES_USER`, `REDIS_HOST_PASSWORD` and `SMTP_PASSWORD`.
 
 # Make your Nextcloud available from the internet
 Until here, your Nextcloud is just available from your docker host. If you want your Nextcloud available from the internet adding SSL encryption is mandatory.