diff --git a/chrome/browser/ui/webui/side_panel/read_anything/read_anything_untrusted_page_handler.cc b/chrome/browser/ui/webui/side_panel/read_anything/read_anything_untrusted_page_handler.cc
index 48171adf0f59c..0fc422a10c318 100644
--- a/chrome/browser/ui/webui/side_panel/read_anything/read_anything_untrusted_page_handler.cc
+++ b/chrome/browser/ui/webui/side_panel/read_anything/read_anything_untrusted_page_handler.cc
@@ -958,6 +958,15 @@ void ReadAnythingUntrustedPageHandler::OnReadAloudAudioStateChange(
                                        : main_observer_->web_contents();
   if (contents) {
     if (playing) {
+      // The renderer is chrome-untrusted; do not trust its assertion that
+      // audio is playing. Read Aloud is implemented via window.speechSynthesis
+      // so the browser-side TtsController is authoritative. Only register the
+      // target tab as audible if speech is actually active. (Mirrors the
+      // AudibilityBypassAuthorization gate added for the
+      // MediaPlayerObserverHostImpl path.)
+      if (!content::TtsController::GetInstance()->IsSpeaking()) {
+        return;
+      }
       audible_closure_ = contents->MarkAudible();
     } else {
       audible_closure_.RunAndReset();