diff --git a/esphome/components/web_server/web_server.cpp b/esphome/components/web_server/web_server.cpp
index c7a0639382..3acd2d2119 100644
--- a/esphome/components/web_server/web_server.cpp
+++ b/esphome/components/web_server/web_server.cpp
@@ -198,7 +198,8 @@ EntityMatchResult UrlMatch::match_entity(EntityBase *entity) const {
 
 #if !defined(USE_ESP32) && defined(USE_ARDUINO)
 // helper for allowing only unique entries in the queue
-void DeferredUpdateEventSource::deq_push_back_with_dedup_(void *source, message_generator_t *message_generator) {
+void __attribute__((flatten))
+DeferredUpdateEventSource::deq_push_back_with_dedup_(void *source, message_generator_t *message_generator) {
   DeferredEvent item(source, message_generator);
 
   // Use range-based for loop instead of std::find_if to reduce template instantiation overhead and binary size