diff --git a/assets/js/components/Loadpoints/BatteryBoostButton.vue b/assets/js/components/Loadpoints/BatteryBoostButton.vue
index 343df0d6f..ffc29cf03 100644
--- a/assets/js/components/Loadpoints/BatteryBoostButton.vue
+++ b/assets/js/components/Loadpoints/BatteryBoostButton.vue
@@ -2,7 +2,7 @@
 	<button
 		class="root position-relative"
 		tabindex="0"
-		:class="{ active, belowLimit, full }"
+		:class="{ active, belowLimit, batteryHold, full }"
 		:style="{ '--soc': `${adjustedSoc}%` }"
 		:disabled="disabled"
 		:aria-label="ariaLabel"
@@ -17,17 +17,17 @@
 			<div class="progress-bar bg-primary progress-bar-striped progress-bar-animated"></div>
 		</div>
 		<div class="icon-wrapper" :style="iconStyle">
-			<BatteryBoost :active="active && !belowLimit" />
+			<BatteryBoost :active="active && available" />
 		</div>
 		<div class="icon-wrapper text-white" :style="iconActiveStyle">
-			<BatteryBoost :active="active && !belowLimit" />
+			<BatteryBoost :active="active && available" />
 		</div>
 	</button>
 </template>
 
 <script lang="ts">
 import { defineComponent, type PropType } from "vue";
-import { CHARGE_MODE, type Timeout } from "@/types/evcc";
+import { BATTERY_MODE, CHARGE_MODE, type Timeout } from "@/types/evcc";
 import BatteryBoost from "../MaterialIcon/BatteryBoost.vue";
 
 export default defineComponent({
@@ -40,6 +40,7 @@ export default defineComponent({
 		batteryBoostLimit: { type: Number, default: 100 },
 		mode: String as PropType<CHARGE_MODE>,
 		batterySoc: { type: Number, default: 0 },
+		batteryMode: String as PropType<BATTERY_MODE>,
 	},
 	emits: ["updated", "status"],
 	data() {
@@ -66,6 +67,12 @@ export default defineComponent({
 		belowLimit(): boolean {
 			return this.batterySoc < this.batteryBoostLimit;
 		},
+		batteryHold(): boolean {
+			return this.batteryMode === BATTERY_MODE.HOLD;
+		},
+		available(): boolean {
+			return !this.belowLimit && !this.batteryHold;
+		},
 		iconStyle() {
 			return {
 				clipPath: this.active ? `inset(0 0 calc(var(--soc)) 0)` : undefined,
@@ -76,6 +83,7 @@ export default defineComponent({
 		},
 		ariaLabel(): string {
 			const t = (key: string) => this.$t(`main.loadpointSettings.batteryBoost.${key}`);
+			if (this.batteryHold) return t("stateHold");
 			if (this.active) return t("stateActive");
 			if (this.belowLimit) return t("stateBelowLimit");
 			return t("stateReady");
@@ -105,6 +113,12 @@ export default defineComponent({
 				});
 			const newValue = !this.active;
 
+			// battery hold: only show message, don't toggle
+			if (newValue && this.batteryHold) {
+				status("batteryBoostHold");
+				return;
+			}
+
 			// below limit: only show message, don't toggle
 			if (newValue && this.belowLimit) {
 				status("batteryBoostBelowLimit");
@@ -157,7 +171,8 @@ export default defineComponent({
 	color: inherit;
 	opacity: 0.25;
 }
-.root.belowLimit:not(:disabled) {
+.root.belowLimit:not(:disabled),
+.root.batteryHold:not(:disabled) {
 	opacity: 0.5;
 }
 .root:before,
diff --git a/assets/js/components/Loadpoints/Loadpoint.vue b/assets/js/components/Loadpoints/Loadpoint.vue
index 0c9371ab7..22296a37c 100644
--- a/assets/js/components/Loadpoints/Loadpoint.vue
+++ b/assets/js/components/Loadpoints/Loadpoint.vue
@@ -127,6 +127,7 @@ import type {
 	Vehicle,
 	Forecast,
 	SMART_COST_TYPE,
+	BATTERY_MODE,
 } from "@/types/evcc";
 import type { PlanStrategy } from "@/components/ChargingPlans/types";
 
@@ -160,6 +161,7 @@ export default defineComponent({
 		batteryBoostLimit: { type: Number, default: 100 },
 		batteryConfigured: Boolean,
 		batterySoc: Number,
+		batteryMode: String as PropType<BATTERY_MODE>,
 
 		// session
 		sessionEnergy: Number,
diff --git a/assets/js/components/Loadpoints/Loadpoints.vue b/assets/js/components/Loadpoints/Loadpoints.vue
index 52153d4df..f761fa6f6 100644
--- a/assets/js/components/Loadpoints/Loadpoints.vue
+++ b/assets/js/components/Loadpoints/Loadpoints.vue
@@ -31,6 +31,7 @@
 					:pvConfigured="pvConfigured"
 					:batteryConfigured="batteryConfigured"
 					:batterySoc="batterySoc"
+					:batteryMode="batteryMode"
 					:forecast="forecast"
 					class="h-100"
 					:class="{ 'loadpoint-unselected': !selected(loadpoint.id) }"
@@ -67,7 +68,7 @@ import "@h2d2/shopicons/es/filled/lightning";
 
 import Loadpoint from "./Loadpoint.vue";
 import { defineComponent, type PropType } from "vue";
-import type { UiLoadpoint, SMART_COST_TYPE, Timeout, Vehicle } from "@/types/evcc";
+import type { UiLoadpoint, SMART_COST_TYPE, Timeout, Vehicle, BATTERY_MODE } from "@/types/evcc";
 
 export default defineComponent({
 	name: "Loadpoints",
@@ -87,6 +88,7 @@ export default defineComponent({
 		pvConfigured: Boolean,
 		batteryConfigured: Boolean,
 		batterySoc: Number,
+		batteryMode: String as PropType<BATTERY_MODE>,
 		forecast: Object, // as PropType<Forecast>,
 	},
 	emits: ["id-changed"],
diff --git a/assets/js/components/Site/Site.vue b/assets/js/components/Site/Site.vue
index 8effdd186..cd63bc32c 100644
--- a/assets/js/components/Site/Site.vue
+++ b/assets/js/components/Site/Site.vue
@@ -69,6 +69,7 @@
 				:pvConfigured="pvConfigured"
 				:batteryConfigured="batteryConfigured"
 				:batterySoc="batterySoc"
+				:batteryMode="batteryMode"
 				:forecast="forecast"
 				:selectedId="selectedLoadpointId"
 				@id-changed="selectedLoadpointChanged"
@@ -101,6 +102,7 @@ import type {
 	Sponsor,
 	FatalError,
 	EvOpt,
+	BATTERY_MODE,
 } from "@/types/evcc";
 import store from "@/store";
 import type { Grid } from "./types";
@@ -134,7 +136,7 @@ export default defineComponent({
 		batteryDischargeControl: Boolean,
 		batteryGridChargeLimit: { type: [Number, null] as PropType<number | null>, default: null },
 		batteryGridChargeActive: Boolean,
-		batteryMode: String,
+		batteryMode: String as PropType<BATTERY_MODE>,
 		battery: { type: Object as PropType<Battery> },
 		gridCurrents: Array,
 		prioritySoc: Number,
diff --git a/assets/js/components/Vehicles/Vehicle.vue b/assets/js/components/Vehicles/Vehicle.vue
index c0f86587a..df0c7053c 100644
--- a/assets/js/components/Vehicles/Vehicle.vue
+++ b/assets/js/components/Vehicles/Vehicle.vue
@@ -88,7 +88,13 @@ import LimitSocSelect from "./LimitSocSelect.vue";
 import LimitEnergySelect from "./LimitEnergySelect.vue";
 import { distanceUnit, distanceValue } from "@/units.ts";
 import { defineComponent, type PropType } from "vue";
-import { CHARGE_MODE, type Forecast, type VehicleStatus, type Vehicle } from "@/types/evcc";
+import {
+	CHARGE_MODE,
+	type BATTERY_MODE,
+	type Forecast,
+	type VehicleStatus,
+	type Vehicle,
+} from "@/types/evcc";
 import type { PlanStrategy } from "@/components/ChargingPlans/types";
 import BatteryBoostButton from "../Loadpoints/BatteryBoostButton.vue";
 
@@ -121,6 +127,7 @@ export default defineComponent({
 		batteryBoostAvailable: Boolean,
 		batteryBoostLimit: { type: Number, default: 100 },
 		batterySoc: Number,
+		batteryMode: String as PropType<BATTERY_MODE>,
 		enabled: Boolean,
 		heating: Boolean,
 		id: [String, Number],
diff --git a/assets/js/types/evcc.ts b/assets/js/types/evcc.ts
index 20b540c28..8da356ec0 100644
--- a/assets/js/types/evcc.ts
+++ b/assets/js/types/evcc.ts
@@ -78,6 +78,7 @@ export interface State {
   system?: string;
   timezone?: string;
   battery?: Battery;
+  batteryMode?: BATTERY_MODE;
   pv?: Meter[];
   aux?: Meter[];
   ext?: Meter[];
@@ -377,6 +378,13 @@ export enum CHARGE_MODE {
   PV = "pv",
 }
 
+export enum BATTERY_MODE {
+  UNKNOWN = "unknown",
+  NORMAL = "normal",
+  HOLD = "hold",
+  CHARGE = "charge",
+}
+
 export enum PHASES {
   AUTO = 0,
   ONE_PHASE = 1,
diff --git a/i18n/de.json b/i18n/de.json
index 84f51c04b..79fdba52b 100644
--- a/i18n/de.json
+++ b/i18n/de.json
@@ -1156,6 +1156,7 @@
         "once": "Boost ist für diesen Ladevorgang aktiviert.",
         "stateActive": "Batterie Boost aktiv",
         "stateBelowLimit": "Batterie zu niedrig für Boost",
+        "stateHold": "Batterie gesperrt",
         "stateReady": "Batterie Boost bereit"
       },
       "batteryUsage": "Hausbatterie",
@@ -1265,6 +1266,7 @@
       "batteryBoostBelowLimit": "Batterie zu niedrig für Boost.",
       "batteryBoostDisabled": "Batterie Boost deaktiviert.",
       "batteryBoostEnabled": "Boost bis Batterie bei {limit}.",
+      "batteryBoostHold": "Batterie gesperrt. Boost nicht verfügbar.",
       "charging": "Ladevorgang aktiv …",
       "cheapEnergyCharging": "Günstige Energie verfügbar.",
       "cheapEnergyNextStart": "Günstige Energie in {duration}.",
diff --git a/i18n/en.json b/i18n/en.json
index c1086e9bf..9dcf9352c 100644
--- a/i18n/en.json
+++ b/i18n/en.json
@@ -1159,6 +1159,7 @@
         "once": "Boost active for this charging session.",
         "stateActive": "Battery boost active",
         "stateBelowLimit": "Battery too low for boost",
+        "stateHold": "Battery locked",
         "stateReady": "Battery boost ready"
       },
       "batteryUsage": "Home Battery",
@@ -1268,6 +1269,7 @@
       "batteryBoostBelowLimit": "Battery too low for boost.",
       "batteryBoostDisabled": "Battery boost disabled.",
       "batteryBoostEnabled": "Boost until battery at {limit}.",
+      "batteryBoostHold": "Battery locked. Boost not available.",
       "charging": "Charging…",
       "cheapEnergyCharging": "Cheap energy available.",
       "cheapEnergyNextStart": "Cheap energy in {duration}.",
diff --git a/server/mcp/openapi.json b/server/mcp/openapi.json
index c8c86876e..60e0342df 100644
--- a/server/mcp/openapi.json
+++ b/server/mcp/openapi.json
@@ -1089,7 +1089,7 @@
     },
     "/loadpoints/{id}/batteryboost/{enable}": {
       "post": {
-        "description": "Enable or disable battery boost. When active, the maximum available home battery power is added until the home battery is drained to configured SoC limit.",
+        "description": "Enable or disable battery boost. When active, the maximum available home battery power is added until the home battery is drained to configured SoC limit. Note: boost will not work while the battery is on hold (e.g. during fast charging or planned charging with discharge prevention enabled).",
         "externalDocs": {
           "url": "https://docs.evcc.io/en/docs/features/battery#battery-boost"
         },
diff --git a/server/mcp/openapi.md b/server/mcp/openapi.md
index 4b1ad3d3e..6859151b7 100644
--- a/server/mcp/openapi.md
+++ b/server/mcp/openapi.md
@@ -482,7 +482,7 @@ call removeLoadpointVehicle {
 
 ## setLoadpointBatteryBoost
 
-Enable or disable battery boost. When active, the maximum available home battery power is added until the home battery is drained to configured SoC limit.
+Enable or disable battery boost. When active, the maximum available home battery power is added until the home battery is drained to configured SoC limit. Note: boost will not work while the battery is on hold (e.g. during fast charging or planned charging with discharge prevention enabled).
 
 **Tags:** loadpoints
 
diff --git a/server/openapi.yaml b/server/openapi.yaml
index 0be12e2b0..e4963e645 100644
--- a/server/openapi.yaml
+++ b/server/openapi.yaml
@@ -192,7 +192,7 @@ paths:
     post:
       operationId: setLoadpointBatteryBoost
       summary: Set battery boost
-      description: "Enable or disable battery boost. When active, the maximum available home battery power is added until the home battery is drained to configured SoC limit."
+      description: "Enable or disable battery boost. When active, the maximum available home battery power is added until the home battery is drained to configured SoC limit. Note: boost will not work while the battery is on hold (e.g. during fast charging or planned charging with discharge prevention enabled)."
       externalDocs:
         url: https://docs.evcc.io/en/docs/features/battery#battery-boost
       tags:
diff --git a/tests/battery-settings.evcc.yaml b/tests/battery-settings.evcc.yaml
index f9b1eff70..930ddbe28 100755
--- a/tests/battery-settings.evcc.yaml
+++ b/tests/battery-settings.evcc.yaml
@@ -37,6 +37,9 @@ loadpoints:
   - title: Carport
     charger: charger
     mode: now
+  - title: Garage
+    charger: charger2
+    mode: off
 
 chargers:
   - name: charger
@@ -56,6 +59,23 @@ chargers:
       source: js
       script: |
         16
+  - name: charger2
+    type: custom
+    enable:
+      source: js
+      script:
+    enabled:
+      source: js
+      script: |
+        true
+    status:
+      source: js
+      script: |
+        "C"
+    maxcurrent:
+      source: js
+      script: |
+        16
 
 tariffs:
   currency: EUR
diff --git a/tests/boost.spec.ts b/tests/boost.spec.ts
index bbeb07ac2..3e9ec500b 100644
--- a/tests/boost.spec.ts
+++ b/tests/boost.spec.ts
@@ -1,6 +1,13 @@
 import { test, expect } from "@playwright/test";
 import { start, stop, restart, baseUrl } from "./evcc";
-import { expectModalHidden, newLoadpoint, addDemoCharger, ChargerStatus } from "./utils";
+import {
+  expectModalHidden,
+  expectModalVisible,
+  newLoadpoint,
+  addDemoCharger,
+  ChargerStatus,
+  openTopNavigation,
+} from "./utils";
 test.use({ baseURL: baseUrl() });
 
 const CONFIG_BATTERY = "battery-settings.evcc.yaml";
@@ -13,15 +20,12 @@ test.describe("boost", async () => {
   test("activate and deactivate boost in solar mode", async ({ page }) => {
     await start(CONFIG_BATTERY);
     await page.goto("/");
-    const boostButton = page.getByTestId("battery-boost-button");
+    const lp = page.getByTestId("loadpoint").first();
+    const boostButton = lp.getByTestId("battery-boost-button");
     await expect(boostButton).not.toBeVisible();
-    await page
-      .getByTestId("mode")
-      .first()
-      .getByRole("button", { name: "Solar", exact: true })
-      .click();
-    await page.getByTestId("loadpoint-settings-button").nth(1).click();
-    const modal = page.getByTestId("loadpoint-settings-modal");
+    await lp.getByTestId("mode").getByRole("button", { name: "Solar", exact: true }).click();
+    await lp.getByTestId("loadpoint-settings-button").last().click();
+    const modal = page.getByTestId("loadpoint-settings-modal").first();
     await modal.getByTestId("battery-boost-limit").selectOption("20 %");
     await expect(modal.getByTestId("battery-boost")).toContainText(
       "Allow fast charging from home battery until it's drained to 20%."
@@ -41,14 +45,11 @@ test.describe("boost", async () => {
   test("battery too low for boost when limit above soc", async ({ page }) => {
     await start(CONFIG_BATTERY);
     await page.goto("/");
-    const boostButton = page.getByTestId("battery-boost-button");
-    await page
-      .getByTestId("mode")
-      .first()
-      .getByRole("button", { name: "Solar", exact: true })
-      .click();
-    await page.getByTestId("loadpoint-settings-button").nth(1).click();
-    const modal = page.getByTestId("loadpoint-settings-modal");
+    const lp = page.getByTestId("loadpoint").first();
+    const boostButton = lp.getByTestId("battery-boost-button");
+    await lp.getByTestId("mode").getByRole("button", { name: "Solar", exact: true }).click();
+    await lp.getByTestId("loadpoint-settings-button").last().click();
+    const modal = page.getByTestId("loadpoint-settings-modal").first();
     await modal.getByTestId("battery-boost-limit").selectOption("90 %");
     await expect(modal.getByTestId("battery-boost")).toContainText("drained to 90%");
     await page.waitForLoadState("networkidle");
@@ -61,29 +62,61 @@ test.describe("boost", async () => {
   test("boost button disabled in fast mode", async ({ page }) => {
     await start(CONFIG_BATTERY);
     await page.goto("/");
-    const boostButton = page.getByTestId("battery-boost-button");
+    const lp = page.getByTestId("loadpoint").first();
+    const boostButton = lp.getByTestId("battery-boost-button");
     // set a boost limit in solar mode so the boost button appears
-    await page
-      .getByTestId("mode")
-      .first()
-      .getByRole("button", { name: "Solar", exact: true })
-      .click();
-    await page.getByTestId("loadpoint-settings-button").nth(1).click();
-    const modal = page.getByTestId("loadpoint-settings-modal");
+    await lp.getByTestId("mode").getByRole("button", { name: "Solar", exact: true }).click();
+    await lp.getByTestId("loadpoint-settings-button").last().click();
+    const modal = page.getByTestId("loadpoint-settings-modal").first();
     await modal.getByTestId("battery-boost-limit").selectOption("20 %");
     await expect(modal.getByTestId("battery-boost")).toContainText("drained to 20%");
     await page.waitForLoadState("networkidle");
     await modal.getByLabel("Close").click();
     await expectModalHidden(modal);
     // switch to fast mode and verify boost button is disabled
-    await page.getByTestId("mode").first().getByRole("button", { name: "Fast" }).click();
+    await lp.getByTestId("mode").getByRole("button", { name: "Fast" }).click();
     await expect(boostButton).toBeDisabled();
   });
 
+  test("boost button disabled when battery is on hold", async ({ page }) => {
+    await start(CONFIG_BATTERY);
+    await page.goto("/");
+
+    // LP1: set solar mode, configure boost limit
+    const lp1 = page.getByTestId("loadpoint").first();
+    await lp1.getByTestId("mode").getByRole("button", { name: "Solar", exact: true }).click();
+    await lp1.getByTestId("loadpoint-settings-button").last().click();
+    const modal = page.getByTestId("loadpoint-settings-modal").first();
+    await modal.getByTestId("battery-boost-limit").selectOption("0 %");
+    await modal.getByLabel("Close").click();
+    await expectModalHidden(modal);
+
+    // enable "Prevent discharge in fast mode"
+    await openTopNavigation(page);
+    await page.getByTestId("topnavigation-battery").click();
+    const batteryModal = page.getByTestId("battery-settings-modal");
+    await expectModalVisible(batteryModal);
+    await batteryModal.getByLabel("Prevent discharge in fast mode and planned charging.").check();
+    await page.getByRole("button", { name: "Close" }).click();
+    await expectModalHidden(batteryModal);
+
+    // LP2: switch to fast mode → triggers global battery hold
+    const lp2 = page.getByTestId("loadpoint").nth(1);
+    await lp2.getByTestId("mode").getByRole("button", { name: "Fast" }).click();
+
+    // LP1: boost button should show hold state
+    const boostButton = lp1.getByTestId("battery-boost-button");
+    await expect(boostButton).toHaveAttribute("aria-label", "Battery locked");
+
+    // clicking should not change state
+    await boostButton.click();
+    await expect(boostButton).toHaveAttribute("aria-label", "Battery locked");
+  });
+
   test("boost default for ui-created loadpoint", async ({ page }) => {
     await start(CONFIG_BATTERY);
 
-    // create a second loadpoint
+    // create a third loadpoint
     await page.goto("/#/config");
     await newLoadpoint(page, "New Charger");
     await addDemoCharger(page, undefined, ChargerStatus.Connected);
@@ -94,7 +127,7 @@ test.describe("boost", async () => {
     // restart evcc to apply new loadpoint
     await restart(CONFIG_BATTERY);
     await page.goto("/");
-    await expect(page.getByTestId("loadpoint")).toHaveCount(2);
+    await expect(page.getByTestId("loadpoint")).toHaveCount(3);
 
     const lp = page.getByTestId("loadpoint").last();