diff --git a/changelogs/client_server/newsfragments/2392.feature b/changelogs/client_server/newsfragments/2392.feature
new file mode 100644
index 00000000..60be5eee
--- /dev/null
+++ b/changelogs/client_server/newsfragments/2392.feature
@@ -0,0 +1 @@
+The room directory now returns rooms in a server-defined order rather than largest first, as per [MSC4423](https://github.com/matrix-org/matrix-spec-proposals/pull/4423).
\ No newline at end of file
diff --git a/changelogs/server_server/newsfragments/2392.feature b/changelogs/server_server/newsfragments/2392.feature
new file mode 100644
index 00000000..60be5eee
--- /dev/null
+++ b/changelogs/server_server/newsfragments/2392.feature
@@ -0,0 +1 @@
+The room directory now returns rooms in a server-defined order rather than largest first, as per [MSC4423](https://github.com/matrix-org/matrix-spec-proposals/pull/4423).
\ No newline at end of file
diff --git a/data/api/client-server/list_public_rooms.yaml b/data/api/client-server/list_public_rooms.yaml
index c3f0280f..b57ecc8d 100644
--- a/data/api/client-server/list_public_rooms.yaml
+++ b/data/api/client-server/list_public_rooms.yaml
@@ -137,8 +137,12 @@ paths:
       description: |-
         Lists a server's published room directory.
 
-        This API returns paginated responses. The rooms are ordered by the number
-        of joined members, with the largest rooms first.
+        This API returns paginated responses.
+
+        {{% changed-in v="1.19" %}} The server determines the order of the rooms
+        returned by this endpoint. Previously, rooms were ordered with the largest
+        joined member count first. Continuing to order by largest first or another
+        stable order is recommended.
       operationId: getPublicRooms
       parameters:
         - in: query
@@ -177,8 +181,12 @@ paths:
       description: |-
         Lists a server's published room directory with an optional filter.
 
-        This API returns paginated responses. The rooms are ordered by the number
-        of joined members, with the largest rooms first.
+        This API returns paginated responses.
+
+        {{% changed-in v="1.19" %}} The server determines the order of the rooms
+        returned by this endpoint. Previously, rooms were ordered with the largest
+        joined member count first. Continuing to order by largest first or another
+        stable order is recommended.
       operationId: queryPublicRooms
       security:
         - accessTokenQuery: []
diff --git a/data/api/server-server/public_rooms.yaml b/data/api/server-server/public_rooms.yaml
index 41835f5a..eb07c918 100644
--- a/data/api/server-server/public_rooms.yaml
+++ b/data/api/server-server/public_rooms.yaml
@@ -22,8 +22,12 @@ paths:
       description: |-
         Lists the server's published room directory.
 
-        This API returns paginated responses. The rooms are ordered by the number
-        of joined members, with the largest rooms first.
+        This API returns paginated responses.
+
+        {{% changed-in v="1.19" %}} The server determines the order of the rooms
+        returned by this endpoint. Previously, rooms were ordered with the largest
+        joined member count first. Continuing to order by largest first or another
+        stable order is recommended.
 
         This SHOULD not return rooms that are listed on another homeserver's directory,
         just those listed on the receiving homeserver's directory.
@@ -76,8 +80,12 @@ paths:
       description: |-
         Lists the server's published room directory with an optional filter.
 
-        This API returns paginated responses. The rooms are ordered by the number
-        of joined members, with the largest rooms first.
+        This API returns paginated responses.
+
+        {{% changed-in v="1.19" %}} The server determines the order of the rooms
+        returned by this endpoint. Previously, rooms were ordered with the largest
+        joined member count first. Continuing to order by largest first or another
+        stable order is recommended.
       operationId: queryPublicRooms
       security:
         - signedRequest: []