diff --git a/synapse/config/key.py b/synapse/config/key.py
index 1d253328ff..10bb989562 100644
--- a/synapse/config/key.py
+++ b/synapse/config/key.py
@@ -50,6 +50,31 @@ and you should enable 'federation_verify_certificates' in your configuration.
 If you are *sure* you want to do this, set 'accept_keys_insecurely' on the
 trusted_key_server configuration."""
 
+TRUSTED_KEY_SERVER_NOT_CONFIGURED_WARN = """\
+Synapse requires that a list of trusted key servers are specified in order to
+provide signing keys for other servers in the federation.
+
+This homeserver does not have a trusted key server configured in
+homeserver.yaml and will fall back to the default of 'matrix.org'.
+
+Trusted key servers should be long-lived and stable which makes matrix.org a
+good choice for many admins, but some admins may wish to choose another. To
+suppress this warning, the admin should set 'trusted_key_servers' in
+homeserver.yaml to their desired key server and 'suppress_key_server_warning'
+to 'true'.
+
+In a future release the software-defined default will be removed entirely and
+the trusted key server will be defined exclusively by the value of
+'trusted_key_servers'."""
+
+TRUSTED_KEY_SERVER_CONFIGURED_AS_M_ORG_WARN = """\
+This server is configured to use 'matrix.org' as its trusted key server via the
+'trusted_key_servers' config option. 'matrix.org' is a good choice for a key
+server since it is long-lived, stable and trusted. However, some admins may
+wish to use another server for this purpose.
+
+To suppress this warning and continue using 'matrix.org', admins should set
+'suppress_key_server_warning' to 'true' in homeserver.yaml."""
 
 logger = logging.getLogger(__name__)
 
@@ -84,6 +109,7 @@ class KeyConfig(Config):
         self.key_refresh_interval = self.parse_duration(
             config.get("key_refresh_interval", "1d")
         )
+
         suppress_key_server_warning = config.get("suppress_key_server_warning", False)
         key_server_signing_keys_path = config.get("key_server_signing_keys_path")
         if key_server_signing_keys_path:
@@ -95,49 +121,10 @@ class KeyConfig(Config):
 
         # if neither trusted_key_servers nor perspectives are given, use the default.
         if "perspectives" not in config and "trusted_key_servers" not in config:
-            logger.warn(
-                """
-                Synapse requires that a list of trusted key servers are
-                specified in order to provide signing keys for other servers in
-                the federation.
-
-                This homeserver does not have a trusted key server configured in
-                homeserver.yaml and will fall back to the default of
-                'matrix.org'.
-
-                Trusted key servers should be long-lived and stable which
-                makes matrix.org a good choice for many admins, but some admins may
-                wish to choose another. To suppress this warning, the admin
-                should set 'trusted_key_servers' in homeserver.yaml to their
-                desired key server and 'suppress_key_server_warning' to 'true'.
-
-                In a future release the software-defined default will be
-                removed entirely and the trusted key server will be defined
-                exclusively by the value of 'trusted_key_servers'.
-                """
-            )
+            logger.warn(TRUSTED_KEY_SERVER_NOT_CONFIGURED_WARN)
             key_servers = [{"server_name": "matrix.org"}]
         else:
             key_servers = config.get("trusted_key_servers", [])
-            for server in key_servers:
-                if (
-                    server["server_name"] == "matrix.org"
-                    and not suppress_key_server_warning
-                ):
-                    logger.warn(
-                        """
-                        This server is configured to use 'matrix.org' as its
-                        trusted key server via the 'trusted_key_servers' config
-                        option. 'matrix.org' is a good choice for a key server
-                        since it is long-lived, stable and trusted. However, some
-                        admins may wish to use another server for this purpose.
-
-                        To suppress this warning and continue using
-                        'matrix.org', admins should set
-                        'suppress_key_server_warning' to 'true' in
-                        homeserver.yaml.
-                        """
-                    )
 
             if not isinstance(key_servers, list):
                 raise ConfigError(
@@ -145,6 +132,13 @@ class KeyConfig(Config):
                     % (type(key_servers).__name__,)
                 )
 
+            for server in key_servers:
+                if (
+                    server["server_name"] == "matrix.org"
+                    and not suppress_key_server_warning
+                ):
+                    logger.warn(TRUSTED_KEY_SERVER_CONFIGURED_AS_M_ORG_WARN)
+
             # merge the 'perspectives' config into the 'trusted_key_servers' config.
             key_servers.extend(_perspectives_to_key_servers(config))
 
@@ -230,6 +224,10 @@ class KeyConfig(Config):
         # This setting supercedes an older setting named `perspectives`. The old format
         # is still supported for backwards-compatibility, but it is deprecated.
         #
+        # 'trusted_key_servers' defaults to matrix.org, but using it will generate a
+        # warning on start up to suppress this warning set 'suppress_key_server_warning'
+        # to true.
+        #
         # Options for each entry in the list include:
         #
         #    server_name: the name of the server. required.
@@ -253,15 +251,11 @@ class KeyConfig(Config):
         #    verify_keys:
         #      "ed25519:auto": "abcdefghijklmnopqrstuvwxyzabcdefghijklmopqr"
         #  - server_name: "my_other_trusted_server.example.com"
-
-        trusted_key_servers:
-        - server_name: "matrix.org"
-
-        # 'trusted_key_servers' defaults to matrix.org, but using it will generate a
-        # warning on start up to suppress this warning set 'suppress_key_server_warning'
-        # to True.
         #
-        #suppress_key_server_warning: True
+        trusted_key_servers:
+          - server_name: "matrix.org"
+        #
+        #suppress_key_server_warning: true
         #
         # The signing keys to use when acting as a trusted key server. If not specified
         # defaults to the server signing key.