diff --git a/homeassistant/components/ouman_eh_800/config_flow.py b/homeassistant/components/ouman_eh_800/config_flow.py
index 39a348cbb83b..d8cda1ad40a5 100644
--- a/homeassistant/components/ouman_eh_800/config_flow.py
+++ b/homeassistant/components/ouman_eh_800/config_flow.py
@@ -38,6 +38,34 @@ class OumanEh800ConfigFlow(ConfigFlow, domain=DOMAIN):
 
     VERSION = 1
 
+    async def _async_validate_input(self, user_input: dict[str, Any]) -> dict[str, str]:
+        """Normalize the URL, check for duplicates and test the connection.
+
+        Mutates user_input to hold the normalized URL. Returns form errors,
+        empty if validation succeeded.
+        """
+        try:
+            user_input[CONF_URL] = _normalize_url(user_input[CONF_URL])
+        except ValueError:
+            return {CONF_URL: "invalid_url"}
+        self._async_abort_entries_match({CONF_URL: user_input[CONF_URL]})
+        client = OumanEh800Client(
+            session=async_get_clientsession(self.hass),
+            username=user_input[CONF_USERNAME],
+            password=user_input[CONF_PASSWORD],
+            address=user_input[CONF_URL],
+        )
+        try:
+            await client.login()
+        except OumanClientCommunicationError:
+            return {"base": "cannot_connect"}
+        except OumanClientAuthenticationError:
+            return {"base": "invalid_auth"}
+        except Exception:
+            _LOGGER.exception("Unexpected exception")
+            return {"base": "unknown"}
+        return {}
+
     @override
     async def async_step_user(
         self, user_input: dict[str, Any] | None = None
@@ -45,31 +73,8 @@ class OumanEh800ConfigFlow(ConfigFlow, domain=DOMAIN):
         """Handle the initial step."""
         errors: dict[str, str] = {}
         if user_input is not None:
-            try:
-                user_input[CONF_URL] = _normalize_url(user_input[CONF_URL])
-            except ValueError:
-                errors[CONF_URL] = "invalid_url"
-            else:
-                self._async_abort_entries_match({CONF_URL: user_input[CONF_URL]})
-                client = OumanEh800Client(
-                    session=async_get_clientsession(self.hass),
-                    username=user_input[CONF_USERNAME],
-                    password=user_input[CONF_PASSWORD],
-                    address=user_input[CONF_URL],
-                )
-                try:
-                    await client.login()
-                except OumanClientCommunicationError:
-                    errors["base"] = "cannot_connect"
-                except OumanClientAuthenticationError:
-                    errors["base"] = "invalid_auth"
-                except Exception:
-                    _LOGGER.exception("Unexpected exception")
-                    errors["base"] = "unknown"
-                else:
-                    return self.async_create_entry(
-                        title="Ouman EH-800", data=user_input
-                    )
+            if not (errors := await self._async_validate_input(user_input)):
+                return self.async_create_entry(title="Ouman EH-800", data=user_input)
 
         return self.async_show_form(
             step_id="user",
@@ -78,3 +83,23 @@ class OumanEh800ConfigFlow(ConfigFlow, domain=DOMAIN):
             ),
             errors=errors,
         )
+
+    async def async_step_reconfigure(
+        self, user_input: dict[str, Any] | None = None
+    ) -> ConfigFlowResult:
+        """Handle reconfiguration of the integration."""
+        reconfigure_entry = self._get_reconfigure_entry()
+        errors: dict[str, str] = {}
+        if user_input is not None:
+            if not (errors := await self._async_validate_input(user_input)):
+                return self.async_update_reload_and_abort(
+                    reconfigure_entry, data_updates=user_input
+                )
+
+        return self.async_show_form(
+            step_id="reconfigure",
+            data_schema=self.add_suggested_values_to_schema(
+                STEP_USER_DATA_SCHEMA, user_input or reconfigure_entry.data
+            ),
+            errors=errors,
+        )
diff --git a/homeassistant/components/ouman_eh_800/quality_scale.yaml b/homeassistant/components/ouman_eh_800/quality_scale.yaml
index 0675818b938b..8d8b321f2723 100644
--- a/homeassistant/components/ouman_eh_800/quality_scale.yaml
+++ b/homeassistant/components/ouman_eh_800/quality_scale.yaml
@@ -70,7 +70,7 @@ rules:
   entity-translations: done
   exception-translations: todo
   icon-translations: done
-  reconfiguration-flow: todo
+  reconfiguration-flow: done
   repair-issues: todo
   stale-devices:
     status: exempt
diff --git a/homeassistant/components/ouman_eh_800/strings.json b/homeassistant/components/ouman_eh_800/strings.json
index a6865d3eab83..e9f92e4cc842 100644
--- a/homeassistant/components/ouman_eh_800/strings.json
+++ b/homeassistant/components/ouman_eh_800/strings.json
@@ -1,7 +1,8 @@
 {
   "config": {
     "abort": {
-      "already_configured": "[%key:common::config_flow::abort::already_configured_device%]"
+      "already_configured": "[%key:common::config_flow::abort::already_configured_device%]",
+      "reconfigure_successful": "[%key:common::config_flow::abort::reconfigure_successful%]"
     },
     "error": {
       "cannot_connect": "[%key:common::config_flow::error::cannot_connect%]",
@@ -10,6 +11,18 @@
       "unknown": "[%key:common::config_flow::error::unknown%]"
     },
     "step": {
+      "reconfigure": {
+        "data": {
+          "password": "[%key:common::config_flow::data::password%]",
+          "url": "[%key:common::config_flow::data::url%]",
+          "username": "[%key:common::config_flow::data::username%]"
+        },
+        "data_description": {
+          "password": "[%key:component::ouman_eh_800::config::step::user::data_description::password%]",
+          "url": "[%key:component::ouman_eh_800::config::step::user::data_description::url%]",
+          "username": "[%key:component::ouman_eh_800::config::step::user::data_description::username%]"
+        }
+      },
       "user": {
         "data": {
           "password": "[%key:common::config_flow::data::password%]",
diff --git a/tests/components/ouman_eh_800/test_config_flow.py b/tests/components/ouman_eh_800/test_config_flow.py
index f62e9a2f6e84..30083ca6c671 100644
--- a/tests/components/ouman_eh_800/test_config_flow.py
+++ b/tests/components/ouman_eh_800/test_config_flow.py
@@ -154,3 +154,103 @@ async def test_user_flow_already_configured(
 
     assert result["type"] is FlowResultType.ABORT
     assert result["reason"] == "already_configured"
+
+
+@pytest.mark.usefixtures("mock_ouman_client")
+@pytest.mark.parametrize(
+    "new_input",
+    [
+        pytest.param(
+            {
+                CONF_URL: "http://192.168.1.200",
+                CONF_USERNAME: "new-user",
+                CONF_PASSWORD: "new-pass",
+            },
+            id="new_url_and_credentials",
+        ),
+        pytest.param(
+            {**USER_INPUT, CONF_PASSWORD: "new-pass"},
+            id="same_url_new_password",
+        ),
+    ],
+)
+async def test_reconfigure_flow_success(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+    new_input: dict[str, str],
+) -> None:
+    """Test a successful reconfiguration updates the entry data."""
+    mock_config_entry.add_to_hass(hass)
+
+    result = await mock_config_entry.start_reconfigure_flow(hass)
+    assert result["type"] is FlowResultType.FORM
+    assert result["step_id"] == "reconfigure"
+    assert result["errors"] == {}
+
+    result = await hass.config_entries.flow.async_configure(
+        result["flow_id"], new_input
+    )
+
+    assert result["type"] is FlowResultType.ABORT
+    assert result["reason"] == "reconfigure_successful"
+    assert mock_config_entry.data == new_input
+
+
+@pytest.mark.parametrize(
+    ("error", "expected_error"),
+    [
+        (OumanClientCommunicationError("Connection failed"), "cannot_connect"),
+        (OumanClientAuthenticationError("Invalid credentials"), "invalid_auth"),
+        (RuntimeError("Unexpected"), "unknown"),
+    ],
+)
+async def test_reconfigure_flow_errors_recover(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+    mock_ouman_client: AsyncMock,
+    error: Exception,
+    expected_error: str,
+) -> None:
+    """Test that reconfigure errors are surfaced and the flow can recover."""
+    mock_config_entry.add_to_hass(hass)
+    mock_ouman_client.login.side_effect = error
+
+    result = await mock_config_entry.start_reconfigure_flow(hass)
+    result = await hass.config_entries.flow.async_configure(
+        result["flow_id"], USER_INPUT
+    )
+
+    assert result["type"] is FlowResultType.FORM
+    assert result["errors"] == {"base": expected_error}
+
+    mock_ouman_client.login.side_effect = None
+    result = await hass.config_entries.flow.async_configure(
+        result["flow_id"], USER_INPUT
+    )
+
+    assert result["type"] is FlowResultType.ABORT
+    assert result["reason"] == "reconfigure_successful"
+
+
+@pytest.mark.usefixtures("mock_ouman_client")
+async def test_reconfigure_flow_already_configured(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+) -> None:
+    """Test aborting when reconfiguring to the URL of another entry."""
+    mock_config_entry.add_to_hass(hass)
+    other_entry = MockConfigEntry(
+        domain=DOMAIN,
+        title="Ouman EH-800",
+        data={**USER_INPUT, CONF_URL: "http://192.168.1.200"},
+    )
+    other_entry.add_to_hass(hass)
+
+    result = await mock_config_entry.start_reconfigure_flow(hass)
+    result = await hass.config_entries.flow.async_configure(
+        result["flow_id"],
+        {**USER_INPUT, CONF_URL: "http://192.168.1.200"},
+    )
+
+    assert result["type"] is FlowResultType.ABORT
+    assert result["reason"] == "already_configured"