diff --git a/homeassistant/components/autarco/config_flow.py b/homeassistant/components/autarco/config_flow.py
index a66f14047a7..294fa685fb8 100644
--- a/homeassistant/components/autarco/config_flow.py
+++ b/homeassistant/components/autarco/config_flow.py
@@ -2,6 +2,7 @@
 
 from __future__ import annotations
 
+from collections.abc import Mapping
 from typing import Any
 
 from autarco import Autarco, AutarcoAuthenticationError, AutarcoConnectionError
@@ -20,6 +21,12 @@ DATA_SCHEMA = vol.Schema(
     }
 )
 
+STEP_REAUTH_SCHEMA = vol.Schema(
+    {
+        vol.Required(CONF_PASSWORD): str,
+    }
+)
+
 
 class AutarcoConfigFlow(ConfigFlow, domain=DOMAIN):
     """Handle a config flow for Autarco."""
@@ -55,3 +62,40 @@ class AutarcoConfigFlow(ConfigFlow, domain=DOMAIN):
             errors=errors,
             data_schema=DATA_SCHEMA,
         )
+
+    async def async_step_reauth(
+        self, entry_data: Mapping[str, Any]
+    ) -> ConfigFlowResult:
+        """Handle re-authentication request from Autarco."""
+        return await self.async_step_reauth_confirm()
+
+    async def async_step_reauth_confirm(
+        self, user_input: dict[str, Any] | None = None
+    ) -> ConfigFlowResult:
+        """Handle re-authentication confirmation."""
+        errors = {}
+
+        reauth_entry = self._get_reauth_entry()
+        if user_input is not None:
+            client = Autarco(
+                email=reauth_entry.data[CONF_EMAIL],
+                password=user_input[CONF_PASSWORD],
+                session=async_get_clientsession(self.hass),
+            )
+            try:
+                await client.get_account()
+            except AutarcoAuthenticationError:
+                errors["base"] = "invalid_auth"
+            except AutarcoConnectionError:
+                errors["base"] = "cannot_connect"
+            else:
+                return self.async_update_reload_and_abort(
+                    reauth_entry,
+                    data_updates=user_input,
+                )
+        return self.async_show_form(
+            step_id="reauth_confirm",
+            description_placeholders={"email": reauth_entry.data[CONF_EMAIL]},
+            data_schema=STEP_REAUTH_SCHEMA,
+            errors=errors,
+        )
diff --git a/homeassistant/components/autarco/coordinator.py b/homeassistant/components/autarco/coordinator.py
index 5dd19478ae8..dd8786bca25 100644
--- a/homeassistant/components/autarco/coordinator.py
+++ b/homeassistant/components/autarco/coordinator.py
@@ -7,6 +7,7 @@ from typing import NamedTuple
 from autarco import (
     AccountSite,
     Autarco,
+    AutarcoAuthenticationError,
     AutarcoConnectionError,
     Battery,
     Inverter,
@@ -16,6 +17,7 @@ from autarco import (
 
 from homeassistant.config_entries import ConfigEntry
 from homeassistant.core import HomeAssistant
+from homeassistant.exceptions import ConfigEntryAuthFailed
 from homeassistant.helpers.update_coordinator import DataUpdateCoordinator, UpdateFailed
 
 from .const import DOMAIN, LOGGER, SCAN_INTERVAL
@@ -60,8 +62,10 @@ class AutarcoDataUpdateCoordinator(DataUpdateCoordinator[AutarcoData]):
             inverters = await self.client.get_inverters(self.account_site.public_key)
             if site.has_battery:
                 battery = await self.client.get_battery(self.account_site.public_key)
-        except AutarcoConnectionError as error:
-            raise UpdateFailed(error) from error
+        except AutarcoAuthenticationError as err:
+            raise ConfigEntryAuthFailed(err) from err
+        except AutarcoConnectionError as err:
+            raise UpdateFailed(err) from err
         return AutarcoData(
             solar=solar,
             inverters=inverters,
diff --git a/homeassistant/components/autarco/quality_scale.yaml b/homeassistant/components/autarco/quality_scale.yaml
index f0eb4771447..d2e1455af7e 100644
--- a/homeassistant/components/autarco/quality_scale.yaml
+++ b/homeassistant/components/autarco/quality_scale.yaml
@@ -51,7 +51,7 @@ rules:
       This integration only polls data using a coordinator.
       Since the integration is read-only and poll-only (only provide sensor
       data), there is no need to implement parallel updates.
-  reauthentication-flow: todo
+  reauthentication-flow: done
   test-coverage: done
 
   # Gold
diff --git a/homeassistant/components/autarco/strings.json b/homeassistant/components/autarco/strings.json
index 8eda5fe0411..159dbd09781 100644
--- a/homeassistant/components/autarco/strings.json
+++ b/homeassistant/components/autarco/strings.json
@@ -2,7 +2,7 @@
   "config": {
     "step": {
       "user": {
-        "description": "Connect to your Autarco account to get information about your solar panels.",
+        "description": "Connect to your Autarco account, to get information about your sites.",
         "data": {
           "email": "[%key:common::config_flow::data::email%]",
           "password": "[%key:common::config_flow::data::password%]"
@@ -11,6 +11,16 @@
           "email": "The email address of your Autarco account.",
           "password": "The password of your Autarco account."
         }
+      },
+      "reauth_confirm": {
+        "title": "[%key:common::config_flow::title::reauth%]",
+        "description": "The password for {email} is no longer valid.",
+        "data": {
+          "password": "[%key:common::config_flow::data::password%]"
+        },
+        "data_description": {
+          "password": "[%key:component::autarco::config::step::user::data_description::password%]"
+        }
       }
     },
     "error": {
@@ -18,7 +28,8 @@
       "cannot_connect": "[%key:common::config_flow::error::cannot_connect%]"
     },
     "abort": {
-      "already_configured": "[%key:common::config_flow::abort::already_configured_device%]"
+      "already_configured": "[%key:common::config_flow::abort::already_configured_device%]",
+      "reauth_successful": "[%key:common::config_flow::abort::reauth_successful%]"
     }
   },
   "entity": {
diff --git a/tests/components/autarco/test_config_flow.py b/tests/components/autarco/test_config_flow.py
index 621ad7f55c8..47c6a2fb084 100644
--- a/tests/components/autarco/test_config_flow.py
+++ b/tests/components/autarco/test_config_flow.py
@@ -1,6 +1,6 @@
 """Test the Autarco config flow."""
 
-from unittest.mock import AsyncMock
+from unittest.mock import AsyncMock, patch
 
 from autarco import AutarcoAuthenticationError, AutarcoConnectionError
 import pytest
@@ -92,6 +92,7 @@ async def test_exceptions(
     assert result.get("type") is FlowResultType.FORM
     assert result.get("errors") == {"base": error}
 
+    # Recover from error
     mock_autarco_client.get_account.side_effect = None
 
     result = await hass.config_entries.flow.async_configure(
@@ -99,3 +100,72 @@ async def test_exceptions(
         user_input={CONF_EMAIL: "test@autarco.com", CONF_PASSWORD: "test-password"},
     )
     assert result.get("type") is FlowResultType.CREATE_ENTRY
+
+
+async def test_step_reauth(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+    mock_setup_entry: AsyncMock,
+) -> None:
+    """Test reauth flow."""
+    mock_config_entry.add_to_hass(hass)
+    result = await mock_config_entry.start_reauth_flow(hass)
+
+    assert result.get("type") is FlowResultType.FORM
+    assert result.get("step_id") == "reauth_confirm"
+
+    with patch("homeassistant.components.autarco.config_flow.Autarco", autospec=True):
+        result = await hass.config_entries.flow.async_configure(
+            result["flow_id"],
+            user_input={CONF_PASSWORD: "new-password"},
+        )
+
+    assert result.get("type") is FlowResultType.ABORT
+    assert result.get("reason") == "reauth_successful"
+
+    assert len(hass.config_entries.async_entries()) == 1
+    assert mock_config_entry.data[CONF_PASSWORD] == "new-password"
+
+
+@pytest.mark.parametrize(
+    ("exception", "error"),
+    [
+        (AutarcoConnectionError, "cannot_connect"),
+        (AutarcoAuthenticationError, "invalid_auth"),
+    ],
+)
+async def test_step_reauth_exceptions(
+    hass: HomeAssistant,
+    mock_autarco_client: AsyncMock,
+    mock_config_entry: MockConfigEntry,
+    mock_setup_entry: AsyncMock,
+    exception: Exception,
+    error: str,
+) -> None:
+    """Test exceptions in reauth flow."""
+    mock_autarco_client.get_account.side_effect = exception
+    mock_config_entry.add_to_hass(hass)
+    result = await mock_config_entry.start_reauth_flow(hass)
+
+    assert result.get("type") is FlowResultType.FORM
+    assert result.get("step_id") == "reauth_confirm"
+
+    result = await hass.config_entries.flow.async_configure(
+        result["flow_id"],
+        user_input={CONF_PASSWORD: "new-password"},
+    )
+    assert result.get("type") is FlowResultType.FORM
+    assert result.get("errors") == {"base": error}
+
+    # Recover from error
+    mock_autarco_client.get_account.side_effect = None
+
+    result = await hass.config_entries.flow.async_configure(
+        result["flow_id"],
+        user_input={CONF_PASSWORD: "new-password"},
+    )
+    assert result.get("type") is FlowResultType.ABORT
+    assert result.get("reason") == "reauth_successful"
+
+    assert len(hass.config_entries.async_entries()) == 1
+    assert mock_config_entry.data[CONF_PASSWORD] == "new-password"
diff --git a/tests/components/autarco/test_init.py b/tests/components/autarco/test_init.py
index 81c5f947251..2707c53d35f 100644
--- a/tests/components/autarco/test_init.py
+++ b/tests/components/autarco/test_init.py
@@ -4,6 +4,8 @@ from __future__ import annotations
 
 from unittest.mock import AsyncMock
 
+from autarco import AutarcoAuthenticationError
+
 from homeassistant.config_entries import ConfigEntryState
 from homeassistant.core import HomeAssistant
 
@@ -26,3 +28,20 @@ async def test_load_unload_entry(
     await hass.async_block_till_done()
 
     assert mock_config_entry.state is ConfigEntryState.NOT_LOADED
+
+
+async def test_setup_entry_exception(
+    hass: HomeAssistant,
+    mock_autarco_client: AsyncMock,
+    mock_config_entry: MockConfigEntry,
+) -> None:
+    """Test ConfigEntryNotReady when API raises an exception during entry setup."""
+    mock_config_entry.add_to_hass(hass)
+    mock_autarco_client.get_site.side_effect = AutarcoAuthenticationError
+
+    await hass.config_entries.async_setup(mock_config_entry.entry_id)
+    assert mock_config_entry.state is ConfigEntryState.SETUP_ERROR
+
+    flows = hass.config_entries.flow.async_progress()
+    assert len(flows) == 1
+    assert flows[0]["step_id"] == "reauth_confirm"