diff --git a/esphome/core/helpers.cpp b/esphome/core/helpers.cpp
index de673c4052..14810f477e 100644
--- a/esphome/core/helpers.cpp
+++ b/esphome/core/helpers.cpp
@@ -646,6 +646,13 @@ void get_mac_address_into_buffer(std::span<char, 13> buf) {
   format_mac_addr_lower_no_sep(mac, buf.data());
 }
 
+const char *get_mac_address_pretty_into_buffer(std::span<char, 18> buf) {
+  uint8_t mac[6];
+  get_mac_address_raw(mac);
+  format_mac_addr_upper(mac, buf.data());
+  return buf.data();
+}
+
 #ifndef USE_ESP32
 bool has_custom_mac_address() { return false; }
 #endif
diff --git a/esphome/core/helpers.h b/esphome/core/helpers.h
index a05a1817b9..615c7778aa 100644
--- a/esphome/core/helpers.h
+++ b/esphome/core/helpers.h
@@ -1125,12 +1125,7 @@ void get_mac_address_into_buffer(std::span<char, 13> buf);
 /// Get the device MAC address into the given buffer, in colon-separated uppercase hex notation.
 /// Buffer must be exactly 18 bytes (17 for "XX:XX:XX:XX:XX:XX" + null terminator).
 /// Returns pointer to the buffer for convenience.
-inline const char *get_mac_address_pretty_into_buffer(std::span<char, 18> buf) {
-  uint8_t mac[6];
-  get_mac_address_raw(mac);
-  format_mac_addr_upper(mac, buf.data());
-  return buf.data();
-}
+const char *get_mac_address_pretty_into_buffer(std::span<char, 18> buf);
 
 #ifdef USE_ESP32
 /// Set the MAC address to use from the provided byte array (6 bytes).