diff --git a/frontend_tests/node_tests/compose.js b/frontend_tests/node_tests/compose.js
index d089dda504..f4656ea351 100644
--- a/frontend_tests/node_tests/compose.js
+++ b/frontend_tests/node_tests/compose.js
@@ -48,6 +48,7 @@ const render_compose_private_stream_alert = mock_template("compose_private_strea
 
 const compose_closed_ui = zrequire("compose_closed_ui");
 const compose_fade = zrequire("compose_fade");
+const compose_pm_pill = zrequire("compose_pm_pill");
 const compose_state = zrequire("compose_state");
 const compose = zrequire("compose");
 const echo = zrequire("echo");
@@ -614,6 +615,7 @@ test_ui("finish", ({override}) => {
         $("#compose-textarea").val("foobarfoobar");
         compose_state.set_message_type("private");
         override(compose_state, "private_message_recipient", () => "bob@example.com");
+        override(compose_pm_pill, "get_user_ids", () => []);
 
         let compose_finished_event_checked = false;
         $(document).on("compose_finished.zulip", () => {
diff --git a/frontend_tests/node_tests/compose_validate.js b/frontend_tests/node_tests/compose_validate.js
index 32f194e987..6a1b790312 100644
--- a/frontend_tests/node_tests/compose_validate.js
+++ b/frontend_tests/node_tests/compose_validate.js
@@ -213,6 +213,13 @@ test_ui("validate", ({override}) => {
     compose_state.private_message_recipient("bob@example.com");
     assert.ok(compose.validate());
 
+    people.deactivate(bob);
+    assert.ok(!compose.validate());
+    assert.equal(
+        $("#compose-error-msg").html(),
+        $t_html({defaultMessage: "You cannot send messages to deactivated users."}),
+    );
+
     page_params.realm_is_zephyr_mirror_realm = true;
     assert.ok(compose.validate());
     page_params.realm_is_zephyr_mirror_realm = false;
diff --git a/static/js/compose.js b/static/js/compose.js
index b74461c85f..037328c55b 100644
--- a/static/js/compose.js
+++ b/static/js/compose.js
@@ -716,17 +716,18 @@ function validate_stream_message() {
 // The function checks whether the recipients are users of the realm or cross realm users (bots
 // for now)
 function validate_private_message() {
-    if (page_params.realm_private_message_policy === 2) {
-        // Frontend check for for PRIVATE_MESSAGE_POLICY_DISABLED
-        const user_ids = compose_pm_pill.get_user_ids();
-        if (user_ids.length !== 1 || !people.get_by_user_id(user_ids[0]).is_bot) {
-            // Unless we're composing to a bot
-            compose_error.show(
-                $t_html({defaultMessage: "Private messages are disabled in this organization."}),
-                $("#private_message_recipient"),
-            );
-            return false;
-        }
+    const user_ids = compose_pm_pill.get_user_ids();
+
+    if (
+        page_params.realm_private_message_policy === 2 && // Frontend check for for PRIVATE_MESSAGE_POLICY_DISABLED
+        (user_ids.length !== 1 || !people.get_by_user_id(user_ids[0]).is_bot)
+    ) {
+        // Unless we're composing to a bot
+        compose_error.show(
+            $t_html({defaultMessage: "Private messages are disabled in this organization."}),
+            $("#private_message_recipient"),
+        );
+        return false;
     }
 
     if (compose_state.private_message_recipient().length === 0) {
@@ -758,6 +759,22 @@ function validate_private_message() {
         );
         return false;
     }
+
+    for (const user_id of user_ids) {
+        if (!people.is_person_active(user_id)) {
+            context = {full_name: people.get_by_user_id(user_id).full_name};
+            compose_error.show(
+                $t_html(
+                    {defaultMessage: "You cannot send messages to deactivated users."},
+                    context,
+                ),
+                $("#private_message_recipient"),
+            );
+
+            return false;
+        }
+    }
+
     return true;
 }