diff --git a/esphome/components/esp_ldo/__init__.py b/esphome/components/esp_ldo/__init__.py
index f136dd149b..5235a9411e 100644
--- a/esphome/components/esp_ldo/__init__.py
+++ b/esphome/components/esp_ldo/__init__.py
@@ -13,22 +13,63 @@ esp_ldo_ns = cg.esphome_ns.namespace("esp_ldo")
 EspLdo = esp_ldo_ns.class_("EspLdo", cg.Component)
 AdjustAction = esp_ldo_ns.class_("AdjustAction", Action)
 
-CHANNELS = (3, 4)
+CHANNELS = (1, 2, 3, 4)
+CHANNELS_INTERNAL = (1, 2)
 CONF_ADJUSTABLE = "adjustable"
+CONF_ALLOW_INTERNAL_CHANNEL = "allow_internal_channel"
+CONF_PASSTHROUGH = "passthrough"
 
 adjusted_ids = set()
 
+
+def validate_ldo_voltage(value):
+    if isinstance(value, str) and value.lower() == CONF_PASSTHROUGH:
+        return CONF_PASSTHROUGH
+    value = cv.voltage(value)
+    if 0.5 <= value <= 2.7:
+        return value
+    raise cv.Invalid(
+        f"LDO voltage must be in range 0.5V-2.7V or 'passthrough' (bypass mode), got {value}V"
+    )
+
+
+def validate_ldo_config(config):
+    channel = config[CONF_CHANNEL]
+    allow_internal = config[CONF_ALLOW_INTERNAL_CHANNEL]
+    if allow_internal and channel not in CHANNELS_INTERNAL:
+        raise cv.Invalid(
+            f"'{CONF_ALLOW_INTERNAL_CHANNEL}' is only valid for internal channels (1, 2). "
+            f"Channel {channel} is a user-configurable channel — its usage depends on your board schematic.",
+            path=[CONF_ALLOW_INTERNAL_CHANNEL],
+        )
+    if channel in CHANNELS_INTERNAL and not allow_internal:
+        raise cv.Invalid(
+            f"LDO channel {channel} is normally used internally by the chip (flash/PSRAM). "
+            f"Set '{CONF_ALLOW_INTERNAL_CHANNEL}: true' to confirm you know what you are doing.",
+            path=[CONF_CHANNEL],
+        )
+    if config[CONF_VOLTAGE] == CONF_PASSTHROUGH and config[CONF_ADJUSTABLE]:
+        raise cv.Invalid(
+            "Passthrough mode passes the supply voltage directly to the output and does not support "
+            "runtime voltage adjustment.",
+            path=[CONF_ADJUSTABLE],
+        )
+    return config
+
+
 CONFIG_SCHEMA = cv.All(
     cv.ensure_list(
-        cv.COMPONENT_SCHEMA.extend(
-            {
-                cv.GenerateID(): cv.declare_id(EspLdo),
-                cv.Required(CONF_VOLTAGE): cv.All(
-                    cv.voltage, cv.float_range(min=0.5, max=2.7)
-                ),
-                cv.Required(CONF_CHANNEL): cv.one_of(*CHANNELS, int=True),
-                cv.Optional(CONF_ADJUSTABLE, default=False): cv.boolean,
-            }
+        cv.All(
+            cv.COMPONENT_SCHEMA.extend(
+                {
+                    cv.GenerateID(): cv.declare_id(EspLdo),
+                    cv.Required(CONF_VOLTAGE): validate_ldo_voltage,
+                    cv.Required(CONF_CHANNEL): cv.one_of(*CHANNELS, int=True),
+                    cv.Optional(CONF_ADJUSTABLE, default=False): cv.boolean,
+                    cv.Optional(CONF_ALLOW_INTERNAL_CHANNEL, default=False): cv.boolean,
+                }
+            ),
+            validate_ldo_config,
         )
     ),
     cv.only_on_esp32,
@@ -40,7 +81,11 @@ async def to_code(configs):
     for config in configs:
         var = cg.new_Pvariable(config[CONF_ID], config[CONF_CHANNEL])
         await cg.register_component(var, config)
-        cg.add(var.set_voltage(config[CONF_VOLTAGE]))
+        voltage = config[CONF_VOLTAGE]
+        if voltage == CONF_PASSTHROUGH:
+            cg.add(var.set_voltage(3300))
+        else:
+            cg.add(var.set_voltage(int(round(voltage * 1000))))
         cg.add(var.set_adjustable(config[CONF_ADJUSTABLE]))
 
 
diff --git a/esphome/components/esp_ldo/esp_ldo.cpp b/esphome/components/esp_ldo/esp_ldo.cpp
index 2eee855b46..f8ebec1903 100644
--- a/esphome/components/esp_ldo/esp_ldo.cpp
+++ b/esphome/components/esp_ldo/esp_ldo.cpp
@@ -10,32 +10,34 @@ static const char *const TAG = "esp_ldo";
 void EspLdo::setup() {
   esp_ldo_channel_config_t config{};
   config.chan_id = this->channel_;
-  config.voltage_mv = (int) (this->voltage_ * 1000.0f);
+  config.voltage_mv = this->voltage_mv_;
   config.flags.adjustable = this->adjustable_;
   auto err = esp_ldo_acquire_channel(&config, &this->handle_);
   if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to acquire LDO channel %d with voltage %fV", this->channel_, this->voltage_);
+    ESP_LOGE(TAG, "Failed to acquire LDO channel %d with voltage %dmV", this->channel_, this->voltage_mv_);
     this->mark_failed(LOG_STR("Failed to acquire LDO channel"));
   } else {
-    ESP_LOGD(TAG, "Acquired LDO channel %d with voltage %fV", this->channel_, this->voltage_);
+    ESP_LOGD(TAG, "Acquired LDO channel %d with voltage %dmV", this->channel_, this->voltage_mv_);
   }
 }
 void EspLdo::dump_config() {
   ESP_LOGCONFIG(TAG,
                 "ESP LDO Channel %d:\n"
-                "  Voltage: %fV\n"
+                "  Voltage: %dmV\n"
                 "  Adjustable: %s",
-                this->channel_, this->voltage_, YESNO(this->adjustable_));
+                this->channel_, this->voltage_mv_, YESNO(this->adjustable_));
 }
 
 void EspLdo::adjust_voltage(float voltage) {
   if (!std::isfinite(voltage) || voltage < 0.5f || voltage > 2.7f) {
-    ESP_LOGE(TAG, "Invalid voltage %fV for LDO channel %d", voltage, this->channel_);
+    ESP_LOGE(TAG, "Invalid voltage %fV for LDO channel %d (must be 0.5V-2.7V)", voltage, this->channel_);
     return;
   }
-  auto erro = esp_ldo_channel_adjust_voltage(this->handle_, (int) (voltage * 1000.0f));
-  if (erro != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to adjust LDO channel %d to voltage %fV: %s", this->channel_, voltage, esp_err_to_name(erro));
+  int voltage_mv = (int) roundf(voltage * 1000.0f);
+  auto err = esp_ldo_channel_adjust_voltage(this->handle_, voltage_mv);
+  if (err != ESP_OK) {
+    ESP_LOGE(TAG, "Failed to adjust LDO channel %d to voltage %dmV: %s", this->channel_, voltage_mv,
+             esp_err_to_name(err));
   }
 }
 
diff --git a/esphome/components/esp_ldo/esp_ldo.h b/esphome/components/esp_ldo/esp_ldo.h
index 9edd303e16..1a20f1d08a 100644
--- a/esphome/components/esp_ldo/esp_ldo.h
+++ b/esphome/components/esp_ldo/esp_ldo.h
@@ -15,7 +15,7 @@ class EspLdo : public Component {
   void dump_config() override;
 
   void set_adjustable(bool adjustable) { this->adjustable_ = adjustable; }
-  void set_voltage(float voltage) { this->voltage_ = voltage; }
+  void set_voltage(int voltage_mv) { this->voltage_mv_ = voltage_mv; }
   void adjust_voltage(float voltage);
   float get_setup_priority() const override {
     return setup_priority::BUS;  // LDO setup should be done early
@@ -23,7 +23,7 @@ class EspLdo : public Component {
 
  protected:
   int channel_;
-  float voltage_{2.7};
+  int voltage_mv_{2700};
   bool adjustable_{false};
   esp_ldo_channel_handle_t handle_{};
 };
diff --git a/tests/components/esp_ldo/test.esp32-p4-idf.yaml b/tests/components/esp_ldo/test.esp32-p4-idf.yaml
index 38bd6ac411..31d2b8cf7a 100644
--- a/tests/components/esp_ldo/test.esp32-p4-idf.yaml
+++ b/tests/components/esp_ldo/test.esp32-p4-idf.yaml
@@ -3,10 +3,13 @@ esp_ldo:
     channel: 3
     voltage: 2.5V
     adjustable: true
-  - id: ldo_4
+  - id: ldo_4_passthrough
     channel: 4
-    voltage: 2.0V
-    setup_priority: 900
+    voltage: passthrough
+  - id: ldo_1_internal
+    channel: 1
+    voltage: 1.8V
+    allow_internal_channel: true
 
 esphome:
   on_boot: