diff --git a/homeassistant/components/modbus/validators.py b/homeassistant/components/modbus/validators.py
index bdf472e4f76..765ce4d8be3 100644
--- a/homeassistant/components/modbus/validators.py
+++ b/homeassistant/components/modbus/validators.py
@@ -308,7 +308,7 @@ def check_config(config: dict) -> dict:
     ) -> bool:
         """Validate entity."""
         name = entity[CONF_NAME]
-        addr = str(entity[CONF_ADDRESS])
+        addr = f"{hub_name}{entity[CONF_ADDRESS]}"
         scan_interval = entity.get(CONF_SCAN_INTERVAL, DEFAULT_SCAN_INTERVAL)
         if scan_interval < 5:
             _LOGGER.warning(
@@ -335,11 +335,15 @@ def check_config(config: dict) -> dict:
         loc_addr: set[str] = {addr}
 
         if CONF_TARGET_TEMP in entity:
-            loc_addr.add(f"{entity[CONF_TARGET_TEMP]}_{inx}")
+            loc_addr.add(f"{hub_name}{entity[CONF_TARGET_TEMP]}_{inx}")
         if CONF_HVAC_MODE_REGISTER in entity:
-            loc_addr.add(f"{entity[CONF_HVAC_MODE_REGISTER][CONF_ADDRESS]}_{inx}")
+            loc_addr.add(
+                f"{hub_name}{entity[CONF_HVAC_MODE_REGISTER][CONF_ADDRESS]}_{inx}"
+            )
         if CONF_FAN_MODE_REGISTER in entity:
-            loc_addr.add(f"{entity[CONF_FAN_MODE_REGISTER][CONF_ADDRESS]}_{inx}")
+            loc_addr.add(
+                f"{hub_name}{entity[CONF_FAN_MODE_REGISTER][CONF_ADDRESS]}_{inx}"
+            )
 
         dup_addrs = ent_addr.intersection(loc_addr)
         if len(dup_addrs) > 0:
diff --git a/tests/components/modbus/test_init.py b/tests/components/modbus/test_init.py
index 5738268a593..4de9a439a01 100644
--- a/tests/components/modbus/test_init.py
+++ b/tests/components/modbus/test_init.py
@@ -740,6 +740,133 @@ async def test_duplicate_fan_mode_validator(do_config) -> None:
     assert len(do_config[CONF_FAN_MODE_VALUES]) == 2
 
 
+@pytest.mark.parametrize(
+    ("do_config", "sensor_cnt"),
+    [
+        (
+            [
+                {
+                    CONF_NAME: TEST_MODBUS_NAME,
+                    CONF_TYPE: TCP,
+                    CONF_HOST: TEST_MODBUS_HOST,
+                    CONF_PORT: TEST_PORT_TCP,
+                    CONF_TIMEOUT: 3,
+                    CONF_SENSORS: [
+                        {
+                            CONF_NAME: TEST_ENTITY_NAME,
+                            CONF_ADDRESS: 117,
+                            CONF_SLAVE: 0,
+                        },
+                        {
+                            CONF_NAME: TEST_ENTITY_NAME + "1",
+                            CONF_ADDRESS: 119,
+                            CONF_SLAVE: 0,
+                        },
+                    ],
+                },
+            ],
+            2,
+        ),
+        (
+            [
+                {
+                    CONF_NAME: TEST_MODBUS_NAME,
+                    CONF_TYPE: TCP,
+                    CONF_HOST: TEST_MODBUS_HOST,
+                    CONF_PORT: TEST_PORT_TCP,
+                    CONF_TIMEOUT: 3,
+                    CONF_SENSORS: [
+                        {
+                            CONF_NAME: TEST_ENTITY_NAME,
+                            CONF_ADDRESS: 117,
+                            CONF_SLAVE: 0,
+                        },
+                        {
+                            CONF_NAME: TEST_ENTITY_NAME + "1",
+                            CONF_ADDRESS: 117,
+                            CONF_SLAVE: 1,
+                        },
+                    ],
+                },
+            ],
+            2,
+        ),
+        (
+            [
+                {
+                    CONF_NAME: TEST_MODBUS_NAME,
+                    CONF_TYPE: TCP,
+                    CONF_HOST: TEST_MODBUS_HOST,
+                    CONF_PORT: TEST_PORT_TCP,
+                    CONF_TIMEOUT: 3,
+                    CONF_SENSORS: [
+                        {
+                            CONF_NAME: TEST_ENTITY_NAME,
+                            CONF_ADDRESS: 117,
+                            CONF_SLAVE: 0,
+                        },
+                        {
+                            CONF_NAME: TEST_ENTITY_NAME + "1",
+                            CONF_ADDRESS: 117,
+                            CONF_SLAVE: 0,
+                        },
+                    ],
+                },
+            ],
+            1,
+        ),
+        (
+            [
+                {
+                    CONF_NAME: TEST_MODBUS_NAME,
+                    CONF_TYPE: TCP,
+                    CONF_HOST: TEST_MODBUS_HOST,
+                    CONF_PORT: TEST_PORT_TCP,
+                    CONF_TIMEOUT: 3,
+                    CONF_SENSORS: [
+                        {
+                            CONF_NAME: TEST_ENTITY_NAME,
+                            CONF_ADDRESS: 117,
+                            CONF_SLAVE: 0,
+                        },
+                        {
+                            CONF_NAME: TEST_ENTITY_NAME + "1",
+                            CONF_ADDRESS: 119,
+                            CONF_SLAVE: 0,
+                        },
+                    ],
+                },
+                {
+                    CONF_NAME: TEST_MODBUS_NAME + "1",
+                    CONF_TYPE: TCP,
+                    CONF_HOST: TEST_MODBUS_HOST,
+                    CONF_PORT: TEST_PORT_TCP,
+                    CONF_TIMEOUT: 3,
+                    CONF_SENSORS: [
+                        {
+                            CONF_NAME: TEST_ENTITY_NAME,
+                            CONF_ADDRESS: 117,
+                            CONF_SLAVE: 0,
+                        },
+                        {
+                            CONF_NAME: TEST_ENTITY_NAME,
+                            CONF_ADDRESS: 119,
+                            CONF_SLAVE: 0,
+                        },
+                    ],
+                },
+            ],
+            2,
+        ),
+    ],
+)
+async def test_duplicate_addresses(do_config, sensor_cnt) -> None:
+    """Test duplicate entity validator."""
+    check_config(do_config)
+    use_inx = len(do_config) - 1
+    assert len(do_config[use_inx][CONF_SENSORS]) == sensor_cnt
+
+
 @pytest.mark.parametrize(
     "do_config",
     [