diff --git a/changelog.d/14364.bugfix b/changelog.d/14364.bugfix
new file mode 100644
index 000000000..514bf859b
--- /dev/null
+++ b/changelog.d/14364.bugfix
@@ -0,0 +1 @@
+Fix refresh token endpoint to be under /r0 and /v3 instead of /v1. Contributed by Tulir @ Beeper.
diff --git a/synapse/rest/client/login.py b/synapse/rest/client/login.py
index 7774f1967..05706b598 100644
--- a/synapse/rest/client/login.py
+++ b/synapse/rest/client/login.py
@@ -536,7 +536,7 @@ def _get_auth_flow_dict_for_idp(idp: SsoIdentityProvider) -> JsonDict:
 
 
 class RefreshTokenServlet(RestServlet):
-    PATTERNS = (re.compile("^/_matrix/client/v1/refresh$"),)
+    PATTERNS = client_patterns("/refresh$")
 
     def __init__(self, hs: "HomeServer"):
         self._auth_handler = hs.get_auth_handler()
diff --git a/tests/rest/client/test_auth.py b/tests/rest/client/test_auth.py
index 847294dc8..208ec4482 100644
--- a/tests/rest/client/test_auth.py
+++ b/tests/rest/client/test_auth.py
@@ -635,7 +635,7 @@ class RefreshAuthTests(unittest.HomeserverTestCase):
         """
         return self.make_request(
             "POST",
-            "/_matrix/client/v1/refresh",
+            "/_matrix/client/v3/refresh",
             {"refresh_token": refresh_token},
         )
 
@@ -724,7 +724,7 @@ class RefreshAuthTests(unittest.HomeserverTestCase):
 
         refresh_response = self.make_request(
             "POST",
-            "/_matrix/client/v1/refresh",
+            "/_matrix/client/v3/refresh",
             {"refresh_token": login_response.json_body["refresh_token"]},
         )
         self.assertEqual(refresh_response.code, HTTPStatus.OK, refresh_response.result)
@@ -765,7 +765,7 @@ class RefreshAuthTests(unittest.HomeserverTestCase):
 
         refresh_response = self.make_request(
             "POST",
-            "/_matrix/client/v1/refresh",
+            "/_matrix/client/v3/refresh",
             {"refresh_token": login_response.json_body["refresh_token"]},
         )
         self.assertEqual(refresh_response.code, HTTPStatus.OK, refresh_response.result)
@@ -1002,7 +1002,7 @@ class RefreshAuthTests(unittest.HomeserverTestCase):
         # This first refresh should work properly
         first_refresh_response = self.make_request(
             "POST",
-            "/_matrix/client/v1/refresh",
+            "/_matrix/client/v3/refresh",
             {"refresh_token": login_response.json_body["refresh_token"]},
         )
         self.assertEqual(
@@ -1012,7 +1012,7 @@ class RefreshAuthTests(unittest.HomeserverTestCase):
         # This one as well, since the token in the first one was never used
         second_refresh_response = self.make_request(
             "POST",
-            "/_matrix/client/v1/refresh",
+            "/_matrix/client/v3/refresh",
             {"refresh_token": login_response.json_body["refresh_token"]},
         )
         self.assertEqual(
@@ -1022,7 +1022,7 @@ class RefreshAuthTests(unittest.HomeserverTestCase):
         # This one should not, since the token from the first refresh is not valid anymore
         third_refresh_response = self.make_request(
             "POST",
-            "/_matrix/client/v1/refresh",
+            "/_matrix/client/v3/refresh",
             {"refresh_token": first_refresh_response.json_body["refresh_token"]},
         )
         self.assertEqual(
@@ -1056,7 +1056,7 @@ class RefreshAuthTests(unittest.HomeserverTestCase):
         # Now that the access token from the last valid refresh was used once, refreshing with the N-1 token should fail
         fourth_refresh_response = self.make_request(
             "POST",
-            "/_matrix/client/v1/refresh",
+            "/_matrix/client/v3/refresh",
             {"refresh_token": login_response.json_body["refresh_token"]},
         )
         self.assertEqual(
@@ -1068,7 +1068,7 @@ class RefreshAuthTests(unittest.HomeserverTestCase):
         # But refreshing from the last valid refresh token still works
         fifth_refresh_response = self.make_request(
             "POST",
-            "/_matrix/client/v1/refresh",
+            "/_matrix/client/v3/refresh",
             {"refresh_token": second_refresh_response.json_body["refresh_token"]},
         )
         self.assertEqual(