diff --git a/webview-ui/src/components/settings/SettingsView.tsx b/webview-ui/src/components/settings/SettingsView.tsx
index 47e087615e3..1d976500e79 100644
--- a/webview-ui/src/components/settings/SettingsView.tsx
+++ b/webview-ui/src/components/settings/SettingsView.tsx
@@ -39,6 +39,8 @@ import {
 	ImageGenerationProvider,
 } from "@roo-code/types"
 
+import { VSCodeCheckbox } from "@vscode/webview-ui-toolkit/react"
+
 import { vscode } from "@src/utils/vscode"
 import { cn } from "@src/lib/utils"
 import { useAppTranslation } from "@src/i18n/TranslationContext"
@@ -203,6 +205,7 @@ const SettingsView = forwardRef<SettingsViewRef, SettingsViewProps>(({ onDone, t
 		includeCurrentTime,
 		includeCurrentCost,
 		maxGitStatusFiles,
+		lockApiConfigAcrossModes,
 	} = cachedState
 
 	const apiConfiguration = useMemo(() => cachedState.apiConfiguration ?? {}, [cachedState.apiConfiguration])
@@ -430,6 +433,7 @@ const SettingsView = forwardRef<SettingsViewRef, SettingsViewProps>(({ onDone, t
 			vscode.postMessage({ type: "upsertApiConfiguration", text: currentApiConfigName, apiConfiguration })
 			vscode.postMessage({ type: "telemetrySetting", text: telemetrySetting })
 			vscode.postMessage({ type: "debugSetting", bool: cachedState.debug })
+			vscode.postMessage({ type: "lockApiConfigAcrossModes", bool: lockApiConfigAcrossModes ?? false })
 
 			setChangeDetected(false)
 		}
@@ -766,6 +770,21 @@ const SettingsView = forwardRef<SettingsViewRef, SettingsViewProps>(({ onDone, t
 											})
 										}
 									/>
+									<div className="mt-2 mb-3">
+										<VSCodeCheckbox
+											checked={lockApiConfigAcrossModes ?? false}
+											onChange={(e: any) =>
+												setCachedStateField("lockApiConfigAcrossModes", e.target.checked)
+											}
+											data-testid="lock-api-config-across-modes-checkbox">
+											<span className="font-medium">
+												{t("settings:providers.lockApiConfigAcrossModes")}
+											</span>
+										</VSCodeCheckbox>
+										<div className="text-vscode-descriptionForeground text-sm mt-1 ml-5">
+											{t("settings:providers.lockApiConfigAcrossModesDescription")}
+										</div>
+									</div>
 									<ApiOptions
 										uriScheme={uriScheme}
 										apiConfiguration={apiConfiguration}
diff --git a/webview-ui/src/components/settings/__tests__/SettingsView.lockApiConfig.spec.tsx b/webview-ui/src/components/settings/__tests__/SettingsView.lockApiConfig.spec.tsx
new file mode 100644
index 00000000000..520b1b19738
--- /dev/null
+++ b/webview-ui/src/components/settings/__tests__/SettingsView.lockApiConfig.spec.tsx
@@ -0,0 +1,361 @@
+// pnpm --filter @roo-code/vscode-webview test src/components/settings/__tests__/SettingsView.lockApiConfig.spec.tsx
+
+import { render, screen, fireEvent, within } from "@/utils/test-utils"
+import { QueryClient, QueryClientProvider } from "@tanstack/react-query"
+
+import { vscode } from "@/utils/vscode"
+import { ExtensionStateContextProvider } from "@/context/ExtensionStateContext"
+
+import SettingsView from "../SettingsView"
+
+vi.mock("@src/utils/vscode", () => ({ vscode: { postMessage: vi.fn() } }))
+
+vi.mock("../ApiConfigManager", () => ({
+	__esModule: true,
+	default: ({ currentApiConfigName }: any) => (
+		<div data-testid="api-config-management">
+			<span>Current config: {currentApiConfigName}</span>
+		</div>
+	),
+}))
+
+vi.mock("@vscode/webview-ui-toolkit/react", () => ({
+	VSCodeButton: ({ children, onClick, appearance, "data-testid": dataTestId }: any) =>
+		appearance === "icon" ? (
+			<button
+				onClick={onClick}
+				className="codicon codicon-close"
+				aria-label="Remove command"
+				data-testid={dataTestId}>
+				<span className="codicon codicon-close" />
+			</button>
+		) : (
+			<button onClick={onClick} data-appearance={appearance} data-testid={dataTestId}>
+				{children}
+			</button>
+		),
+	VSCodeCheckbox: ({ children, onChange, checked, "data-testid": dataTestId }: any) => (
+		<label>
+			<input
+				type="checkbox"
+				checked={checked}
+				onChange={(e) => onChange({ target: { checked: e.target.checked } })}
+				aria-label={typeof children === "string" ? children : undefined}
+				data-testid={dataTestId}
+			/>
+			{children}
+		</label>
+	),
+	VSCodeTextField: ({ value, onInput, placeholder, "data-testid": dataTestId }: any) => (
+		<input
+			type="text"
+			value={value}
+			onChange={(e) => onInput?.({ target: { value: e.target.value } })}
+			placeholder={placeholder}
+			data-testid={dataTestId}
+		/>
+	),
+	VSCodeLink: ({ children, href }: any) => <a href={href || "#"}>{children}</a>,
+	VSCodeRadio: ({ value, checked, onChange }: any) => (
+		<input type="radio" value={value} checked={checked} onChange={onChange} />
+	),
+	VSCodeRadioGroup: ({ children, onChange }: any) => <div onChange={onChange}>{children}</div>,
+	VSCodeTextArea: ({ value, onChange, rows, className, "data-testid": dataTestId }: any) => (
+		<textarea
+			value={value}
+			onChange={onChange}
+			rows={rows}
+			className={className}
+			data-testid={dataTestId}
+			role="textbox"
+		/>
+	),
+}))
+
+vi.mock("../../../components/common/Tab", () => ({
+	...vi.importActual("../../../components/common/Tab"),
+	Tab: ({ children }: any) => <div data-testid="tab-container">{children}</div>,
+	TabHeader: ({ children }: any) => <div data-testid="tab-header">{children}</div>,
+	TabContent: ({ children, "data-testid": dataTestId }: any) => (
+		<div data-testid={dataTestId || "tab-content"}>{children}</div>
+	),
+	TabList: ({ children, value, onValueChange, "data-testid": dataTestId }: any) => {
+		;(window as any).__onValueChange = onValueChange
+		return (
+			<div data-testid={dataTestId} data-value={value}>
+				{children}
+			</div>
+		)
+	},
+	TabTrigger: ({ children, value, "data-testid": dataTestId, onClick, isSelected }: any) => {
+		const handleClick = () => {
+			if (onClick) onClick()
+			const onValueChange = (window as any).__onValueChange
+			if (onValueChange) onValueChange(value)
+		}
+
+		return (
+			<button data-testid={dataTestId} data-value={value} data-selected={isSelected} onClick={handleClick}>
+				{children}
+			</button>
+		)
+	},
+}))
+
+vi.mock("@/components/ui", async (importOriginal) => {
+	const actual = await importOriginal()
+	return {
+		...(actual as any),
+		ToggleSwitch: ({ checked, onChange, "aria-label": ariaLabel, "data-testid": dataTestId }: any) => (
+			<button
+				role="switch"
+				aria-checked={checked}
+				aria-label={ariaLabel}
+				data-testid={dataTestId}
+				onClick={onChange}>
+				Toggle
+			</button>
+		),
+		Checkbox: ({ checked, onCheckedChange, id, className, ...props }: any) => (
+			<input
+				type="checkbox"
+				checked={checked}
+				onChange={(e) => onCheckedChange?.(e.target.checked)}
+				id={id}
+				className={className}
+				{...props}
+			/>
+		),
+		Textarea: ({ value, onChange, placeholder, id, className, ...props }: any) => (
+			<textarea
+				value={value}
+				onChange={onChange}
+				placeholder={placeholder}
+				id={id}
+				className={className}
+				{...props}
+			/>
+		),
+		StandardTooltip: ({ children }: any) => <>{children}</>,
+		Tooltip: ({ children }: any) => <>{children}</>,
+		TooltipContent: ({ children }: any) => <>{children}</>,
+		TooltipProvider: ({ children }: any) => <>{children}</>,
+		TooltipTrigger: ({ children }: any) => <>{children}</>,
+		Input: ({ value, onChange, placeholder, "data-testid": dataTestId }: any) => (
+			<input type="text" value={value} onChange={onChange} placeholder={placeholder} data-testid={dataTestId} />
+		),
+		Button: ({ children, onClick, ...props }: any) => (
+			<button onClick={onClick} {...props}>
+				{children}
+			</button>
+		),
+		SearchableSelect: ({ value, onValueChange, options, placeholder }: any) => (
+			<select value={value} onChange={(e) => onValueChange(e.target.value)} data-testid="searchable-select">
+				{placeholder && <option value="">{placeholder}</option>}
+				{options?.map((opt: any) => (
+					<option key={opt.value} value={opt.value}>
+						{opt.label}
+					</option>
+				))}
+			</select>
+		),
+		AlertDialog: ({ children, open }: any) => (
+			<div data-testid="alert-dialog" data-open={open}>
+				{children}
+			</div>
+		),
+		AlertDialogContent: ({ children }: any) => <div data-testid="alert-dialog-content">{children}</div>,
+		AlertDialogHeader: ({ children }: any) => <div data-testid="alert-dialog-header">{children}</div>,
+		AlertDialogTitle: ({ children }: any) => <div data-testid="alert-dialog-title">{children}</div>,
+		AlertDialogDescription: ({ children }: any) => <div data-testid="alert-dialog-description">{children}</div>,
+		AlertDialogFooter: ({ children }: any) => <div data-testid="alert-dialog-footer">{children}</div>,
+		AlertDialogAction: ({ children, onClick }: any) => (
+			<button data-testid="alert-dialog-action" onClick={onClick}>
+				{children}
+			</button>
+		),
+		AlertDialogCancel: ({ children, onClick }: any) => (
+			<button data-testid="alert-dialog-cancel" onClick={onClick}>
+				{children}
+			</button>
+		),
+		Collapsible: ({ children, open }: any) => (
+			<div className="collapsible-mock" data-open={open}>
+				{children}
+			</div>
+		),
+		CollapsibleTrigger: ({ children, className, onClick }: any) => (
+			<div className={`collapsible-trigger-mock ${className || ""}`} onClick={onClick}>
+				{children}
+			</div>
+		),
+		CollapsibleContent: ({ children, className }: any) => (
+			<div className={`collapsible-content-mock ${className || ""}`}>{children}</div>
+		),
+		Dialog: ({ children, ...props }: any) => (
+			<div data-testid="dialog" {...props}>
+				{children}
+			</div>
+		),
+		DialogContent: ({ children, ...props }: any) => (
+			<div data-testid="dialog-content" {...props}>
+				{children}
+			</div>
+		),
+		DialogHeader: ({ children, ...props }: any) => (
+			<div data-testid="dialog-header" {...props}>
+				{children}
+			</div>
+		),
+		DialogTitle: ({ children, ...props }: any) => (
+			<div data-testid="dialog-title" {...props}>
+				{children}
+			</div>
+		),
+		DialogDescription: ({ children, ...props }: any) => (
+			<div data-testid="dialog-description" {...props}>
+				{children}
+			</div>
+		),
+		DialogFooter: ({ children, ...props }: any) => (
+			<div data-testid="dialog-footer" {...props}>
+				{children}
+			</div>
+		),
+	}
+})
+
+vi.mock("vscrui", () => ({
+	Checkbox: ({ children, checked, onChange }: any) => (
+		<label>
+			<input type="checkbox" checked={checked} onChange={(e) => onChange(e.target.checked)} />
+			{children}
+		</label>
+	),
+}))
+
+vi.mock("../ApiOptions", () => ({
+	__esModule: true,
+	default: () => <div data-testid="api-options">ApiOptions</div>,
+}))
+
+const mockPostMessage = (state: any) => {
+	window.postMessage(
+		{
+			type: "state",
+			state: {
+				version: "1.0.0",
+				clineMessages: [],
+				taskHistory: [],
+				shouldShowAnnouncement: false,
+				allowedCommands: [],
+				alwaysAllowExecute: false,
+				ttsEnabled: false,
+				ttsSpeed: 1,
+				soundEnabled: false,
+				soundVolume: 0.5,
+				lockApiConfigAcrossModes: false,
+				...state,
+			},
+		},
+		"*",
+	)
+}
+
+const renderSettingsView = (initialState: any = {}) => {
+	const onDone = vi.fn()
+	const queryClient = new QueryClient()
+
+	const result = render(
+		<ExtensionStateContextProvider>
+			<QueryClientProvider client={queryClient}>
+				<SettingsView onDone={onDone} targetSection="providers" />
+			</QueryClientProvider>
+		</ExtensionStateContextProvider>,
+	)
+
+	// Hydrate initial state
+	mockPostMessage(initialState)
+
+	const getSettingsContent = () => screen.getByTestId("settings-content")
+
+	return { onDone, getSettingsContent, result, queryClient }
+}
+
+describe("SettingsView - Lock API Config Across Modes", () => {
+	beforeEach(() => {
+		vi.clearAllMocks()
+	})
+
+	it("renders the lock API config checkbox in the providers tab", () => {
+		const { getSettingsContent } = renderSettingsView()
+		const content = getSettingsContent()
+		const checkbox = within(content).getByTestId("lock-api-config-across-modes-checkbox")
+		expect(checkbox).toBeInTheDocument()
+	})
+
+	it("initializes with lockApiConfigAcrossModes unchecked by default", () => {
+		const { getSettingsContent } = renderSettingsView()
+		const content = getSettingsContent()
+		const checkbox = within(content).getByTestId("lock-api-config-across-modes-checkbox")
+		expect(checkbox).not.toBeChecked()
+	})
+
+	it("toggles the checkbox when clicked", () => {
+		const { getSettingsContent } = renderSettingsView()
+		const content = getSettingsContent()
+		const checkbox = within(content).getByTestId("lock-api-config-across-modes-checkbox")
+
+		// Initially unchecked
+		expect(checkbox).not.toBeChecked()
+
+		// Click to enable
+		fireEvent.click(checkbox)
+		expect(checkbox).toBeChecked()
+
+		// Click to disable
+		fireEvent.click(checkbox)
+		expect(checkbox).not.toBeChecked()
+	})
+
+	it("sends lockApiConfigAcrossModes=true message when saving with checkbox enabled", () => {
+		const { getSettingsContent } = renderSettingsView()
+		const content = getSettingsContent()
+
+		// Enable the lock checkbox
+		const checkbox = within(content).getByTestId("lock-api-config-across-modes-checkbox")
+		fireEvent.click(checkbox)
+
+		// Click Save
+		const saveButton = screen.getByTestId("save-button")
+		fireEvent.click(saveButton)
+
+		expect(vscode.postMessage).toHaveBeenCalledWith(
+			expect.objectContaining({
+				type: "lockApiConfigAcrossModes",
+				bool: true,
+			}),
+		)
+	})
+
+	it("sends lockApiConfigAcrossModes=false message when saving with checkbox disabled", () => {
+		const { getSettingsContent } = renderSettingsView()
+		const content = getSettingsContent()
+
+		// Enable then disable the lock checkbox
+		const checkbox = within(content).getByTestId("lock-api-config-across-modes-checkbox")
+		fireEvent.click(checkbox) // enable
+		fireEvent.click(checkbox) // disable
+
+		// Click Save
+		const saveButton = screen.getByTestId("save-button")
+		fireEvent.click(saveButton)
+
+		expect(vscode.postMessage).toHaveBeenCalledWith(
+			expect.objectContaining({
+				type: "lockApiConfigAcrossModes",
+				bool: false,
+			}),
+		)
+	})
+})
diff --git a/webview-ui/src/i18n/locales/en/settings.json b/webview-ui/src/i18n/locales/en/settings.json
index 8ec42367f14..9cbd586f9e2 100644
--- a/webview-ui/src/i18n/locales/en/settings.json
+++ b/webview-ui/src/i18n/locales/en/settings.json
@@ -351,6 +351,8 @@
 		"providerDocumentation": "{{provider}} documentation",
 		"configProfile": "Configuration Profile",
 		"description": "Save different API configurations to quickly switch between providers and settings.",
+		"lockApiConfigAcrossModes": "Use the same API configuration for all modes",
+		"lockApiConfigAcrossModesDescription": "When enabled, switching modes (e.g. Ask, Code, Architect) will not change the selected provider or model. The lock icon in the API Configuration popover does the same thing.",
 		"apiProvider": "API Provider",
 		"apiProviderDocs": "Provider Docs",
 		"model": "Model",