diff --git a/esphome/components/esp32/preferences.cpp b/esphome/components/esp32/preferences.cpp
index 02d7edb606..e19a85e4e3 100644
--- a/esphome/components/esp32/preferences.cpp
+++ b/esphome/components/esp32/preferences.cpp
@@ -14,18 +14,14 @@ namespace esp32 {
 
 static const char *const TAG = "esp32.preferences";
 
-// Max uint32_t is "4294967295" (10 chars) + null terminator + 1 padding
-static constexpr size_t PREF_KEY_SIZE = 12;
+// Buffer size for converting uint32_t to string: max "4294967295" (10 chars) + null terminator + 1 padding
+static constexpr size_t KEY_BUFFER_SIZE = 12;
 
 struct NVSData {
-  char key[PREF_KEY_SIZE];
+  uint32_t key;
   std::unique_ptr<uint8_t[]> data;
   size_t len;
 
-  void set_key(const char *k) {
-    strncpy(this->key, k, sizeof(this->key) - 1);
-    this->key[sizeof(this->key) - 1] = '\0';
-  }
   void set_data(const uint8_t *src, size_t size) {
     this->data = std::make_unique<uint8_t[]>(size);
     memcpy(this->data.get(), src, size);
@@ -37,27 +33,27 @@ static std::vector<NVSData> s_pending_save;  // NOLINT(cppcoreguidelines-avoid-n
 
 class ESP32PreferenceBackend : public ESPPreferenceBackend {
  public:
-  char key[PREF_KEY_SIZE];
+  uint32_t key;
   uint32_t nvs_handle;
   bool save(const uint8_t *data, size_t len) override {
     // try find in pending saves and update that
     for (auto &obj : s_pending_save) {
-      if (strcmp(obj.key, this->key) == 0) {
+      if (obj.key == this->key) {
         obj.set_data(data, len);
         return true;
       }
     }
     NVSData save{};
-    save.set_key(this->key);
+    save.key = this->key;
     save.set_data(data, len);
     s_pending_save.emplace_back(std::move(save));
-    ESP_LOGVV(TAG, "s_pending_save: key: %s, len: %zu", this->key, len);
+    ESP_LOGVV(TAG, "s_pending_save: key: %" PRIu32 ", len: %zu", this->key, len);
     return true;
   }
   bool load(uint8_t *data, size_t len) override {
     // try find in pending saves and load from that
     for (auto &obj : s_pending_save) {
-      if (strcmp(obj.key, this->key) == 0) {
+      if (obj.key == this->key) {
         if (obj.len != len) {
           // size mismatch
           return false;
@@ -67,22 +63,24 @@ class ESP32PreferenceBackend : public ESPPreferenceBackend {
       }
     }
 
+    char key_str[KEY_BUFFER_SIZE];
+    snprintf(key_str, sizeof(key_str), "%" PRIu32, this->key);
     size_t actual_len;
-    esp_err_t err = nvs_get_blob(this->nvs_handle, this->key, nullptr, &actual_len);
+    esp_err_t err = nvs_get_blob(this->nvs_handle, key_str, nullptr, &actual_len);
     if (err != 0) {
-      ESP_LOGV(TAG, "nvs_get_blob('%s'): %s - the key might not be set yet", this->key, esp_err_to_name(err));
+      ESP_LOGV(TAG, "nvs_get_blob('%s'): %s - the key might not be set yet", key_str, esp_err_to_name(err));
       return false;
     }
     if (actual_len != len) {
       ESP_LOGVV(TAG, "NVS length does not match (%zu!=%zu)", actual_len, len);
       return false;
     }
-    err = nvs_get_blob(this->nvs_handle, this->key, data, &len);
+    err = nvs_get_blob(this->nvs_handle, key_str, data, &len);
     if (err != 0) {
-      ESP_LOGV(TAG, "nvs_get_blob('%s') failed: %s", this->key, esp_err_to_name(err));
+      ESP_LOGV(TAG, "nvs_get_blob('%s') failed: %s", key_str, esp_err_to_name(err));
       return false;
     } else {
-      ESP_LOGVV(TAG, "nvs_get_blob: key: %s, len: %zu", this->key, len);
+      ESP_LOGVV(TAG, "nvs_get_blob: key: %s, len: %zu", key_str, len);
     }
     return true;
   }
@@ -109,13 +107,12 @@ class ESP32Preferences : public ESPPreferences {
     }
   }
   ESPPreferenceObject make_preference(size_t length, uint32_t type, bool in_flash) override {
-    return make_preference(length, type);
+    return this->make_preference(length, type);
   }
   ESPPreferenceObject make_preference(size_t length, uint32_t type) override {
     auto *pref = new ESP32PreferenceBackend();  // NOLINT(cppcoreguidelines-owning-memory)
     pref->nvs_handle = this->nvs_handle;
-
-    snprintf(pref->key, sizeof(pref->key), "%" PRIu32, type);
+    pref->key = type;
 
     return ESPPreferenceObject(pref);
   }
@@ -128,25 +125,27 @@ class ESP32Preferences : public ESPPreferences {
     // goal try write all pending saves even if one fails
     int cached = 0, written = 0, failed = 0;
     esp_err_t last_err = ESP_OK;
-    char last_key[PREF_KEY_SIZE] = {};
+    uint32_t last_key = 0;
 
     // go through vector from back to front (makes erase easier/more efficient)
     for (ssize_t i = s_pending_save.size() - 1; i >= 0; i--) {
       const auto &save = s_pending_save[i];
-      ESP_LOGVV(TAG, "Checking if NVS data %s has changed", save.key);
+      ESP_LOGVV(TAG, "Checking if NVS data %" PRIu32 " has changed", save.key);
       if (this->is_changed(this->nvs_handle, save)) {
-        esp_err_t err = nvs_set_blob(this->nvs_handle, save.key, save.data.get(), save.len);
-        ESP_LOGV(TAG, "sync: key: %s, len: %zu", save.key, save.len);
+        char key_str[KEY_BUFFER_SIZE];
+        snprintf(key_str, sizeof(key_str), "%" PRIu32, save.key);
+        esp_err_t err = nvs_set_blob(this->nvs_handle, key_str, save.data.get(), save.len);
+        ESP_LOGV(TAG, "sync: key: %s, len: %zu", key_str, save.len);
         if (err != 0) {
-          ESP_LOGV(TAG, "nvs_set_blob('%s', len=%zu) failed: %s", save.key, save.len, esp_err_to_name(err));
+          ESP_LOGV(TAG, "nvs_set_blob('%s', len=%zu) failed: %s", key_str, save.len, esp_err_to_name(err));
           failed++;
           last_err = err;
-          strncpy(last_key, save.key, sizeof(last_key) - 1);
+          last_key = save.key;
           continue;
         }
         written++;
       } else {
-        ESP_LOGV(TAG, "NVS data not changed skipping %s  len=%zu", save.key, save.len);
+        ESP_LOGV(TAG, "NVS data not changed skipping %" PRIu32 "  len=%zu", save.key, save.len);
         cached++;
       }
       s_pending_save.erase(s_pending_save.begin() + i);
@@ -154,7 +153,8 @@ class ESP32Preferences : public ESPPreferences {
     ESP_LOGD(TAG, "Writing %d items: %d cached, %d written, %d failed", cached + written + failed, cached, written,
              failed);
     if (failed > 0) {
-      ESP_LOGE(TAG, "Writing %d items failed. Last error=%s for key=%s", failed, esp_err_to_name(last_err), last_key);
+      ESP_LOGE(TAG, "Writing %d items failed. Last error=%s for key=%" PRIu32, failed, esp_err_to_name(last_err),
+               last_key);
     }
 
     // note: commit on esp-idf currently is a no-op, nvs_set_blob always writes
@@ -167,10 +167,13 @@ class ESP32Preferences : public ESPPreferences {
     return failed == 0;
   }
   bool is_changed(const uint32_t nvs_handle, const NVSData &to_save) {
+    char key_str[KEY_BUFFER_SIZE];
+    snprintf(key_str, sizeof(key_str), "%" PRIu32, to_save.key);
+
     size_t actual_len;
-    esp_err_t err = nvs_get_blob(nvs_handle, to_save.key, nullptr, &actual_len);
+    esp_err_t err = nvs_get_blob(nvs_handle, key_str, nullptr, &actual_len);
     if (err != 0) {
-      ESP_LOGV(TAG, "nvs_get_blob('%s'): %s - the key might not be set yet", to_save.key, esp_err_to_name(err));
+      ESP_LOGV(TAG, "nvs_get_blob('%s'): %s - the key might not be set yet", key_str, esp_err_to_name(err));
       return true;
     }
     // Check size first before allocating memory
@@ -178,9 +181,9 @@ class ESP32Preferences : public ESPPreferences {
       return true;
     }
     auto stored_data = std::make_unique<uint8_t[]>(actual_len);
-    err = nvs_get_blob(nvs_handle, to_save.key, stored_data.get(), &actual_len);
+    err = nvs_get_blob(nvs_handle, key_str, stored_data.get(), &actual_len);
     if (err != 0) {
-      ESP_LOGV(TAG, "nvs_get_blob('%s') failed: %s", to_save.key, esp_err_to_name(err));
+      ESP_LOGV(TAG, "nvs_get_blob('%s') failed: %s", key_str, esp_err_to_name(err));
       return true;
     }
     return memcmp(to_save.data.get(), stored_data.get(), to_save.len) != 0;