diff --git a/esphome/components/wifi/wifi_component.h b/esphome/components/wifi/wifi_component.h
index 33263bbdfe..514aabc249 100644
--- a/esphome/components/wifi/wifi_component.h
+++ b/esphome/components/wifi/wifi_component.h
@@ -161,6 +161,9 @@ struct EAPAuth {
 
 using bssid_t = std::array<uint8_t, 6>;
 
+/// Initial reserve size for filtered scan results (typical: 1-3 matching networks per SSID)
+static constexpr size_t WIFI_SCAN_RESULT_FILTERED_RESERVE = 8;
+
 // Use std::vector for RP2040 (callback-based) and ESP32 (destructive scan API)
 // Use FixedVector for ESP8266 and LibreTiny where two-pass exact allocation is possible
 #if defined(USE_RP2040) || defined(USE_ESP32)
diff --git a/esphome/components/wifi/wifi_component_esp_idf.cpp b/esphome/components/wifi/wifi_component_esp_idf.cpp
index 5a7fbd35f0..cdc101b87c 100644
--- a/esphome/components/wifi/wifi_component_esp_idf.cpp
+++ b/esphome/components/wifi/wifi_component_esp_idf.cpp
@@ -833,7 +833,7 @@ void WiFiComponent::wifi_process_event_(IDFWiFiEvent *data) {
     if (needs_full) {
       this->scan_result_.reserve(number);
     } else {
-      this->scan_result_.reserve(8);  // Typical: 1-3 matching networks
+      this->scan_result_.reserve(WIFI_SCAN_RESULT_FILTERED_RESERVE);
     }
 
     // Process one record at a time to avoid large buffer allocation