diff --git a/web/src/compose_closed_ui.js b/web/src/compose_closed_ui.js
index f28d046dff..47d59899f9 100644
--- a/web/src/compose_closed_ui.js
+++ b/web/src/compose_closed_ui.js
@@ -38,11 +38,7 @@ export function get_recipient_label(message) {
                 return format_stream_recipient_label(stream_id, topic);
             } else if (narrow_state.pm_ids_string()) {
                 const user_ids = people.user_ids_string_to_ids_array(narrow_state.pm_ids_string());
-                const user_ids_dicts = user_ids.map((user_id) => ({id: user_id}));
-                return message_store.get_pm_full_names({
-                    type: "private",
-                    display_recipient: user_ids_dicts,
-                });
+                return message_store.get_pm_full_names(user_ids);
             }
         } else {
             message = message_lists.current.selected_message();
diff --git a/web/src/message_helper.js b/web/src/message_helper.js
index 7c6626bd91..d25fe99827 100644
--- a/web/src/message_helper.js
+++ b/web/src/message_helper.js
@@ -58,7 +58,9 @@ export function process_new_message(message) {
         case "private":
             message.is_private = true;
             message.reply_to = util.normalize_recipients(message_store.get_pm_emails(message));
-            message.display_reply_to = message_store.get_pm_full_names(message);
+            message.display_reply_to = message_store.get_pm_full_names(
+                people.pm_with_user_ids(message),
+            );
             message.pm_with_url = people.pm_with_url(message);
             message.to_user_ids = people.pm_reply_user_string(message);
 
diff --git a/web/src/message_list_view.js b/web/src/message_list_view.js
index 5141a26834..4440d490c0 100644
--- a/web/src/message_list_view.js
+++ b/web/src/message_list_view.js
@@ -243,7 +243,9 @@ function populate_group_from_message_container(group, message_container) {
     } else if (group.is_private) {
         group.pm_with_url = message_container.pm_with_url;
         group.recipient_users = get_users_for_recipient_row(message_container.msg);
-        group.display_reply_to_for_tooltip = message_store.get_pm_full_names(message_container.msg);
+        group.display_reply_to_for_tooltip = message_store.get_pm_full_names(
+            people.pm_with_user_ids(message_container.msg),
+        );
     }
     group.display_recipient = message_container.msg.display_recipient;
     group.topic_links = message_container.msg.topic_links;
diff --git a/web/src/message_store.ts b/web/src/message_store.ts
index 3f0e092c51..4924c4aa21 100644
--- a/web/src/message_store.ts
+++ b/web/src/message_store.ts
@@ -184,8 +184,8 @@ export function get_pm_emails(message: Message): string {
     return emails.join(", ");
 }
 
-export function get_pm_full_names(message: Message): string {
-    const user_ids = people.pm_with_user_ids(message) ?? [];
+export function get_pm_full_names(user_ids: number[]): string {
+    user_ids = people.sorted_other_user_ids(user_ids);
     const names = people.get_display_full_names(user_ids).sort();
 
     return names.join(", ");
diff --git a/web/src/people.ts b/web/src/people.ts
index 31087d44ac..828f1e7e7b 100644
--- a/web/src/people.ts
+++ b/web/src/people.ts
@@ -513,7 +513,7 @@ export function pm_reply_to(message: Message): string | undefined {
     return reply_to;
 }
 
-function sorted_other_user_ids(user_ids: number[]): number[] {
+export function sorted_other_user_ids(user_ids: number[]): number[] {
     // This excludes your own user id unless you're the only user
     // (i.e. you sent a message to yourself).
 
diff --git a/web/tests/message_store.test.js b/web/tests/message_store.test.js
index e816cf40bc..2ea485b6f7 100644
--- a/web/tests/message_store.test.js
+++ b/web/tests/message_store.test.js
@@ -226,7 +226,7 @@ test("errors", ({disallow_rewire}) => {
 
     assert.throws(
         () => {
-            message_store.get_pm_full_names(message);
+            message_store.get_pm_full_names(people.pm_with_user_ids(message));
         },
         {
             name: "Error",