diff --git a/docs/sample_config.yaml b/docs/sample_config.yaml
index 274658bfb2..a084a6d720 100644
--- a/docs/sample_config.yaml
+++ b/docs/sample_config.yaml
@@ -1093,7 +1093,7 @@ account_validity:
 # pending invites for the given 3PID (and then allow it to sign up on
 # the platform):
 #
-#allow_invited_3pids: False
+#allow_invited_3pids: false
 #
 #allowed_local_3pids:
 #  - medium: email
@@ -1106,7 +1106,7 @@ account_validity:
 # If true, stop users from trying to change the 3PIDs associated with
 # their accounts.
 #
-#disable_3pid_changes: False
+#disable_3pid_changes: false
 
 # Enable 3PIDs lookup requests to identity servers from this server.
 #
@@ -1178,8 +1178,8 @@ account_validity:
 # Useful when provisioning users based on the contents of a 3rd party
 # directory and to avoid ambiguities.
 #
-#disable_set_displayname: False
-#disable_set_avatar_url: False
+#disable_set_displayname: false
+#disable_set_avatar_url: false
 
 # Handle threepid (email/phone etc) registration and password resets through a set of
 # *trusted* identity servers. Note that this allows the configured identity server to
diff --git a/synapse/config/registration.py b/synapse/config/registration.py
index 1a44b17589..687433e88a 100644
--- a/synapse/config/registration.py
+++ b/synapse/config/registration.py
@@ -305,7 +305,7 @@ class RegistrationConfig(Config):
         # pending invites for the given 3PID (and then allow it to sign up on
         # the platform):
         #
-        #allow_invited_3pids: False
+        #allow_invited_3pids: false
         #
         #allowed_local_3pids:
         #  - medium: email
@@ -318,7 +318,7 @@ class RegistrationConfig(Config):
         # If true, stop users from trying to change the 3PIDs associated with
         # their accounts.
         #
-        #disable_3pid_changes: False
+        #disable_3pid_changes: false
 
         # Enable 3PIDs lookup requests to identity servers from this server.
         #
@@ -390,8 +390,8 @@ class RegistrationConfig(Config):
         # Useful when provisioning users based on the contents of a 3rd party
         # directory and to avoid ambiguities.
         #
-        #disable_set_displayname: False
-        #disable_set_avatar_url: False
+        #disable_set_displayname: false
+        #disable_set_avatar_url: false
 
         # Handle threepid (email/phone etc) registration and password resets through a set of
         # *trusted* identity servers. Note that this allows the configured identity server to