diff --git a/esphome/components/tsl2591/sensor.py b/esphome/components/tsl2591/sensor.py
index 63a0733365..5435ed4b62 100644
--- a/esphome/components/tsl2591/sensor.py
+++ b/esphome/components/tsl2591/sensor.py
@@ -24,6 +24,7 @@ import esphome.config_validation as cv
 from esphome.components import i2c, sensor
 from esphome.const import (
     CONF_GAIN,
+    CONF_ACTUAL_GAIN,
     CONF_ID,
     CONF_NAME,
     CONF_INTEGRATION_TIME,
@@ -79,7 +80,6 @@ TSL2591Component = tsl2591_ns.class_(
     "TSL2591Component", cg.PollingComponent, i2c.I2CDevice
 )
 
-
 CONFIG_SCHEMA = (
     cv.Schema(
         {
@@ -106,6 +106,12 @@ CONFIG_SCHEMA = (
                 device_class=DEVICE_CLASS_ILLUMINANCE,
                 state_class=STATE_CLASS_MEASUREMENT,
             ),
+            cv.Optional(CONF_ACTUAL_GAIN): sensor.sensor_schema(
+                icon=ICON_BRIGHTNESS_6,
+                accuracy_decimals=0,
+                device_class=DEVICE_CLASS_ILLUMINANCE,
+                state_class=STATE_CLASS_MEASUREMENT,
+            ),
             cv.Optional(
                 CONF_INTEGRATION_TIME, default="100ms"
             ): validate_integration_time,
@@ -150,6 +156,11 @@ async def to_code(config):
         sens = await sensor.new_sensor(conf)
         cg.add(var.set_calculated_lux_sensor(sens))
 
+    if CONF_ACTUAL_GAIN in config:
+        conf = config[CONF_ACTUAL_GAIN]
+        sens = await sensor.new_sensor(conf)
+        cg.add(var.set_actual_gain_sensor(sens))
+
     cg.add(var.set_name(config[CONF_NAME]))
     cg.add(var.set_power_save_mode(config[CONF_POWER_SAVE_MODE]))
     cg.add(var.set_integration_time(config[CONF_INTEGRATION_TIME]))
diff --git a/esphome/components/tsl2591/tsl2591.cpp b/esphome/components/tsl2591/tsl2591.cpp
index e3df467aeb..5086a38408 100644
--- a/esphome/components/tsl2591/tsl2591.cpp
+++ b/esphome/components/tsl2591/tsl2591.cpp
@@ -130,6 +130,7 @@ void TSL2591Component::dump_config() {
   LOG_SENSOR("  ", "Infrared:", this->infrared_sensor_);
   LOG_SENSOR("  ", "Visible:", this->visible_sensor_);
   LOG_SENSOR("  ", "Calculated lux:", this->calculated_lux_sensor_);
+  LOG_SENSOR("  ", "Actual gain:", this->actual_gain_sensor_);
 
   LOG_UPDATE_INTERVAL(this);
 }
@@ -140,8 +141,9 @@ void TSL2591Component::process_update_() {
   uint16_t infrared = this->get_illuminance(TSL2591_SENSOR_CHANNEL_INFRARED, combined);
   uint16_t full = this->get_illuminance(TSL2591_SENSOR_CHANNEL_FULL_SPECTRUM, combined);
   float lux = this->get_calculated_lux(full, infrared);
-  ESP_LOGD(TAG, "Got illuminance: combined 0x%X, full %d, IR %d, vis %d. Calc lux: %f", combined, full, infrared,
-           visible, lux);
+  uint16_t actual_gain = this->get_actual_gain();
+  ESP_LOGD(TAG, "Got illuminance: combined 0x%X, full %d, IR %d, vis %d. Calc lux: %f. Actual gain: %d.", combined,
+           full, infrared, visible, lux, actual_gain);
   if (this->full_spectrum_sensor_ != nullptr) {
     this->full_spectrum_sensor_->publish_state(full);
   }
@@ -154,9 +156,14 @@ void TSL2591Component::process_update_() {
   if (this->calculated_lux_sensor_ != nullptr) {
     this->calculated_lux_sensor_->publish_state(lux);
   }
+
   if (this->component_gain_ == TSL2591_CGAIN_AUTO) {
     this->automatic_gain_update(full);
   }
+
+  if (this->actual_gain_sensor_ != nullptr) {
+    this->actual_gain_sensor_->publish_state(actual_gain);
+  }
   this->status_clear_warning();
 }
 
@@ -207,6 +214,10 @@ void TSL2591Component::set_calculated_lux_sensor(sensor::Sensor *calculated_lux_
   this->calculated_lux_sensor_ = calculated_lux_sensor;
 }
 
+void TSL2591Component::set_actual_gain_sensor(sensor::Sensor *actual_gain_sensor) {
+  this->actual_gain_sensor_ = actual_gain_sensor;
+}
+
 void TSL2591Component::set_integration_time(TSL2591IntegrationTime integration_time) {
   this->integration_time_ = integration_time;
 }
@@ -377,7 +388,6 @@ float TSL2591Component::get_calculated_lux(uint16_t full_spectrum, uint16_t infr
       again = 1.0F;
       break;
   }
-
   // This lux equation is copied from the Adafruit TSL2591 v1.4.0 and modified slightly.
   // See: https://github.com/adafruit/Adafruit_TSL2591_Library/issues/14
   // and that library code.
@@ -448,5 +458,25 @@ void TSL2591Component::automatic_gain_update(uint16_t full_spectrum) {
   ESP_LOGD(TAG, "Gain setting: %d", this->gain_);
 }
 
+/** Reads the actual gain used
+ *
+ * Useful for exposing the real gain used when configured in "auto" gain mode
+ */
+float TSL2591Component::get_actual_gain() {
+  switch (this->gain_) {
+    case TSL2591_GAIN_LOW:
+      return 1.0F;
+    case TSL2591_GAIN_MED:
+      return 25.0F;
+    case TSL2591_GAIN_HIGH:
+      return 400.0F;
+    case TSL2591_GAIN_MAX:
+      return 9500.0F;
+    default:
+      // Shouldn't get here, but just in case.
+      return NAN;
+  }
+}
+
 }  // namespace tsl2591
 }  // namespace esphome
diff --git a/esphome/components/tsl2591/tsl2591.h b/esphome/components/tsl2591/tsl2591.h
index 5b7eea35ec..d7c5230276 100644
--- a/esphome/components/tsl2591/tsl2591.h
+++ b/esphome/components/tsl2591/tsl2591.h
@@ -217,14 +217,21 @@ class TSL2591Component : public PollingComponent, public i2c::I2CDevice {
    *
    * This gets called on update and tries to keep the ADC readings in the middle of the range
    */
-
   void automatic_gain_update(uint16_t full_spectrum);
 
+  /** Reads the actual gain used
+   *
+   * Useful for exposing the real gain used when configured in "auto" gain mode
+   */
+  float get_actual_gain();
+
   // ========== INTERNAL METHODS ==========
   // (In most use cases you won't need these. They're for ESPHome integration use.)
   /** Used by ESPHome framework. */
   void set_full_spectrum_sensor(sensor::Sensor *full_spectrum_sensor);
   /** Used by ESPHome framework. */
+  void set_actual_gain_sensor(sensor::Sensor *actual_gain_sensor);
+  /** Used by ESPHome framework. */
   void set_infrared_sensor(sensor::Sensor *infrared_sensor);
   /** Used by ESPHome framework. */
   void set_visible_sensor(sensor::Sensor *visible_sensor);
@@ -249,6 +256,7 @@ class TSL2591Component : public PollingComponent, public i2c::I2CDevice {
   sensor::Sensor *infrared_sensor_{nullptr};
   sensor::Sensor *visible_sensor_{nullptr};
   sensor::Sensor *calculated_lux_sensor_{nullptr};
+  sensor::Sensor *actual_gain_sensor_{nullptr};
   TSL2591IntegrationTime integration_time_;
   TSL2591ComponentGain component_gain_;
   TSL2591Gain gain_;
diff --git a/esphome/const.py b/esphome/const.py
index 5662531a5e..6c898ff3ec 100644
--- a/esphome/const.py
+++ b/esphome/const.py
@@ -26,6 +26,7 @@ CONF_ACTION_ID = "action_id"
 CONF_ACTION_STATE_TOPIC = "action_state_topic"
 CONF_ACTIVE = "active"
 CONF_ACTIVE_POWER = "active_power"
+CONF_ACTUAL_GAIN = "actual_gain"
 CONF_ADDRESS = "address"
 CONF_ADDRESSABLE_LIGHT_ID = "addressable_light_id"
 CONF_ADVANCED = "advanced"