diff --git a/esphome/components/mdns/mdns_component.cpp b/esphome/components/mdns/mdns_component.cpp
index 5dfaa7fd4b..8945053b7d 100644
--- a/esphome/components/mdns/mdns_component.cpp
+++ b/esphome/components/mdns/mdns_component.cpp
@@ -9,7 +9,6 @@
 #include <pgmspace.h>
 // Macro to define strings in PROGMEM on ESP8266, regular memory on other platforms
 #define MDNS_STATIC_CONST_CHAR(name, value) static const char name[] PROGMEM = value
-#define MDNS_STR(name) (reinterpret_cast<const MDNSString *>(name))
 // Helper to convert PROGMEM string to std::string for TemplatableValue
 // Only define this function if we have services that will use it
 #if defined(USE_API) || defined(USE_PROMETHEUS) || defined(USE_WEBSERVER) || defined(USE_MDNS_EXTRA_SERVICES)
@@ -24,7 +23,6 @@ static std::string mdns_str_value(PGM_P str) {
 #else
 // On non-ESP8266 platforms, use regular const char*
 #define MDNS_STATIC_CONST_CHAR(name, value) static constexpr const char name[] = value
-#define MDNS_STR(name) (reinterpret_cast<const MDNSString *>(name))
 #define MDNS_STR_VALUE(name) std::string(name)
 #endif
 
diff --git a/esphome/components/mdns/mdns_component.h b/esphome/components/mdns/mdns_component.h
index ef366cd31a..09f6d36a80 100644
--- a/esphome/components/mdns/mdns_component.h
+++ b/esphome/components/mdns/mdns_component.h
@@ -12,6 +12,9 @@ namespace mdns {
 // Helper struct that identifies strings that may be stored in flash storage (similar to LogString)
 struct MDNSString;
 
+// Macro to cast string literals to MDNSString* (works on all platforms)
+#define MDNS_STR(name) (reinterpret_cast<const MDNSString *>(name))
+
 #ifdef USE_ESP8266
 #include <pgmspace.h>
 #define MDNS_STR_ARG(s) ((PGM_P) (s))