diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 80600ae5..c1398b7d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -29,5 +29,9 @@ jobs:
       - name: Run TypeScript type checking
         run: bunx turbo run check-types --filter='@supermemory/ai-sdk' --filter='@supermemory/memory-graph'
 
+      - name: Run web unit tests
+        working-directory: apps/web
+        run: bun test
+
       - name: Run Biome CI (format & lint on changed files)
         run: bunx biome ci --changed --since=origin/main --no-errors-on-unmatched
diff --git a/apps/web/app/(app)/onboarding/page.test.tsx b/apps/web/app/(app)/onboarding/page.test.tsx
new file mode 100644
index 00000000..ab7d367d
--- /dev/null
+++ b/apps/web/app/(app)/onboarding/page.test.tsx
@@ -0,0 +1,319 @@
+import {
+	afterAll,
+	afterEach,
+	beforeEach,
+	describe,
+	expect,
+	it,
+	mock,
+} from "bun:test"
+import type { ReactNode } from "react"
+import { Window } from "happy-dom"
+import { onboardingDraftKey } from "@/lib/brain-onboarding-draft"
+
+type AboutValues = {
+	name: string
+	about: string
+	workspaceName: string
+	workspaceDomain: string
+}
+
+type AboutProps = {
+	values: AboutValues
+	onChange: (values: AboutValues) => void
+	onContinue: () => void | Promise<void>
+}
+
+type CreateOrganizationInput = {
+	name: string
+	slug: string
+	metadata: Record<string, unknown> & { brainAbout?: string }
+}
+
+const browserWindow = new Window({
+	url: "https://app.supermemory.ai/onboarding",
+})
+const browserGlobals = [
+	"window",
+	"document",
+	"navigator",
+	"Node",
+	"HTMLElement",
+	"Event",
+	"MutationObserver",
+	"localStorage",
+] as const
+const originalDescriptors = new Map(
+	browserGlobals.map((name) => [
+		name,
+		Object.getOwnPropertyDescriptor(globalThis, name),
+	]),
+)
+const originalActEnvironment = Object.getOwnPropertyDescriptor(
+	globalThis,
+	"IS_REACT_ACT_ENVIRONMENT",
+)
+
+for (const name of browserGlobals) {
+	Object.defineProperty(globalThis, name, {
+		configurable: true,
+		value: browserWindow[name],
+	})
+}
+Object.defineProperty(globalThis, "IS_REACT_ACT_ENVIRONMENT", {
+	configurable: true,
+	value: true,
+})
+
+const React = await import("react")
+
+const accountA = {
+	id: "user-a",
+	name: "Alice A",
+	email: "alice@gmail.com",
+	image: null,
+}
+const accountB = {
+	id: "user-b",
+	name: "Bob B",
+	email: "bob@gmail.com",
+	image: null,
+}
+let currentUser = accountA
+let latestAboutProps: AboutProps | null = null
+
+const router = { push: mock(), replace: mock() }
+const searchParams = new URLSearchParams()
+const setActiveOrg = mock(async () => {})
+const refetchOrganizations = mock(async () => {})
+const createOrganization = mock(async (_input: CreateOrganizationInput) => ({
+	data: { slug: "created-workspace" },
+	error: null,
+}))
+const updateUser = mock(async () => ({ data: {}, error: null }))
+
+mock.module("next/navigation", () => ({
+	useRouter: () => router,
+	useSearchParams: () => searchParams,
+}))
+
+mock.module("@tanstack/react-query", () => ({
+	useQueryClient: () => ({ invalidateQueries: mock() }),
+}))
+
+mock.module("sonner", () => ({
+	toast: { error: mock(), success: mock() },
+}))
+
+mock.module("@lib/auth-context", () => ({
+	useAuth: () => ({
+		user: currentUser,
+		session: { id: `session-${currentUser.id}` },
+		isSessionPending: false,
+		isRestoring: false,
+		org: null,
+		organizations: [],
+		setActiveOrg,
+		refetchOrganizations,
+	}),
+}))
+
+mock.module("@lib/auth", () => ({
+	authClient: {
+		organization: {
+			create: createOrganization,
+			inviteMember: mock(async () => ({ data: {}, error: null })),
+		},
+		updateUser,
+	},
+}))
+
+mock.module("@lib/constants", () => ({
+	SHARED_TEAM_BRAIN_TAG: "sm_org_shared",
+}))
+
+mock.module("@/lib/analytics", () => ({
+	analytics: new Proxy({} as Record<string, () => void>, {
+		get: () => () => {},
+	}),
+}))
+
+mock.module("@/lib/company-brain-entry", () => ({
+	resolveCompanyBrainEntry: () => ({ action: "create" }),
+}))
+
+mock.module("@/components/onboarding-brain/shell", () => ({
+	BrainShell: ({ children }: { children: ReactNode }) =>
+		React.createElement("main", null, children),
+}))
+
+mock.module("@/components/onboarding-brain/step-about", () => ({
+	StepAbout: (props: AboutProps) => {
+		latestAboutProps = props
+		return React.createElement("output", null, JSON.stringify(props.values))
+	},
+}))
+
+mock.module("@/components/onboarding-brain/step-sources", () => ({
+	StepSources: () => null,
+}))
+mock.module("@/components/onboarding-brain/step-ingest", () => ({
+	StepIngest: () => null,
+}))
+mock.module("@/components/onboarding-brain/step-team", () => ({
+	StepTeam: () => null,
+}))
+mock.module("@/components/onboarding-brain/company-brain-onboarding", () => ({
+	CompanyBrainOnboarding: () => null,
+}))
+
+const [{ act }, { createRoot }, { default: BrainOnboardingPage }] =
+	await Promise.all([
+		import("react"),
+		import("react-dom/client"),
+		import("./page"),
+	])
+
+let root: ReturnType<typeof createRoot> | null = null
+let container: HTMLElement | null = null
+
+function aboutProps(): AboutProps {
+	if (!latestAboutProps) throw new Error("StepAbout was not rendered")
+	return latestAboutProps
+}
+
+async function renderPage() {
+	await act(async () => {
+		root?.render(React.createElement(BrainOnboardingPage))
+		await Promise.resolve()
+	})
+}
+
+beforeEach(() => {
+	currentUser = accountA
+	latestAboutProps = null
+	localStorage.clear()
+	for (const key of [...searchParams.keys()]) searchParams.delete(key)
+	createOrganization.mockClear()
+	updateUser.mockClear()
+	router.push.mockClear()
+	router.replace.mockClear()
+
+	container = document.createElement("div")
+	document.body.append(container)
+	root = createRoot(container)
+})
+
+afterEach(async () => {
+	await act(async () => root?.unmount())
+	container?.remove()
+	root = null
+	container = null
+})
+
+afterAll(() => {
+	for (const name of browserGlobals) {
+		const descriptor = originalDescriptors.get(name)
+		if (descriptor) Object.defineProperty(globalThis, name, descriptor)
+		else Reflect.deleteProperty(globalThis, name)
+	}
+	if (originalActEnvironment) {
+		Object.defineProperty(
+			globalThis,
+			"IS_REACT_ACT_ENVIRONMENT",
+			originalActEnvironment,
+		)
+	} else {
+		Reflect.deleteProperty(globalThis, "IS_REACT_ACT_ENVIRONMENT")
+	}
+	void browserWindow.close()
+})
+
+describe("onboarding draft ownership", () => {
+	it("isolates drafts and mutations across an A to B to A account switch", async () => {
+		localStorage.setItem(
+			"supermemory-brain-onboarding-v1",
+			JSON.stringify({ about: { name: "Unowned legacy draft" } }),
+		)
+		await renderPage()
+
+		const aliceDraft: AboutValues = {
+			name: "Alice Secret",
+			about: "Confidential acquisition planning",
+			workspaceName: "Alice Private Brain",
+			workspaceDomain: "alice.example",
+		}
+
+		await act(async () => {
+			aboutProps().onChange(aliceDraft)
+			await Promise.resolve()
+		})
+		expect(aboutProps().values).toEqual(aliceDraft)
+
+		currentUser = accountB
+		await renderPage()
+
+		const bobValues = aboutProps().values
+		expect(bobValues.name).toBe("Bob B")
+		expect(bobValues.about).toBe("")
+		expect(bobValues.workspaceName).not.toBe(aliceDraft.workspaceName)
+		expect(JSON.stringify(bobValues)).not.toContain("Alice")
+
+		await act(async () => {
+			await aboutProps().onContinue()
+		})
+
+		const createPayload = createOrganization.mock.calls[0]?.[0]
+		expect(createPayload?.name).toBe(bobValues.workspaceName)
+		expect(createPayload?.metadata.brainAbout).toBeUndefined()
+		expect(JSON.stringify(createPayload)).not.toContain("Alice")
+		expect(updateUser).toHaveBeenCalledWith(
+			expect.objectContaining({
+				name: "Bob B",
+				displayUsername: "Bob B",
+			}),
+		)
+
+		currentUser = accountA
+		await renderPage()
+
+		expect(aboutProps().values).toEqual(aliceDraft)
+		expect(localStorage.getItem("supermemory-brain-onboarding-v1")).toBeNull()
+	})
+
+	it("starts a fresh user-owned draft when new workspace mode is forced", async () => {
+		await renderPage()
+		const existingDraft: AboutValues = {
+			name: "Alice Secret",
+			about: "Existing private draft",
+			workspaceName: "Existing Workspace",
+			workspaceDomain: "existing.example",
+		}
+		await act(async () => {
+			aboutProps().onChange(existingDraft)
+			await Promise.resolve()
+		})
+
+		searchParams.set("new", "1")
+		searchParams.set("name", "Fresh Workspace")
+		await renderPage()
+
+		expect(aboutProps().values).toEqual({
+			name: "Alice A",
+			about: "",
+			workspaceName: "Fresh Workspace",
+			workspaceDomain: "",
+		})
+		const persisted = localStorage.getItem(onboardingDraftKey(accountA.id))
+		expect(persisted).not.toBeNull()
+		expect(persisted).not.toContain("Existing private draft")
+
+		searchParams.delete("new")
+		searchParams.delete("name")
+		await renderPage()
+		expect(aboutProps().values.about).toBe("")
+		expect(aboutProps().values.workspaceName).not.toBe(
+			existingDraft.workspaceName,
+		)
+	})
+})
diff --git a/apps/web/app/(app)/onboarding/page.tsx b/apps/web/app/(app)/onboarding/page.tsx
index 1cde19cf..56257eb4 100644
--- a/apps/web/app/(app)/onboarding/page.tsx
+++ b/apps/web/app/(app)/onboarding/page.tsx
@@ -9,6 +9,13 @@ import { authClient } from "@lib/auth"
 import { SHARED_TEAM_BRAIN_TAG } from "@lib/constants"
 import { analytics } from "@/lib/analytics"
 import { resolveCompanyBrainEntry } from "@/lib/company-brain-entry"
+import {
+	clearOnboardingDraft,
+	discardLegacyOnboardingDraft,
+	getOnboardingDraftStorage,
+	readOnboardingDraft,
+	writeOnboardingDraft,
+} from "@/lib/brain-onboarding-draft"
 import { BrainShell } from "@/components/onboarding-brain/shell"
 import {
 	StepAbout,
@@ -39,10 +46,16 @@ import {
 	type CompanyBrainConfirmResult,
 } from "@/components/onboarding-brain/types"
 
-const STORAGE_KEY = "supermemory-brain-onboarding-v1"
 const BACKEND =
 	process.env.NEXT_PUBLIC_BACKEND_URL ?? "https://api.supermemory.ai"
 
+type BrainOnboardingDraft = {
+	mode?: BrainMode
+	about?: AboutValues
+	sources?: SourcesValues
+	team?: TeamValues
+}
+
 const countsAsConnectedSource = (state: unknown) =>
 	state === "connected" || state === "waitlist"
 
@@ -71,6 +84,12 @@ const getWorkspaceCreationErrorCopy = (message: string) => {
 }
 
 export default function BrainOnboardingPage() {
+	const { user } = useAuth()
+	if (!user?.id) return null
+	return <BrainOnboardingContent key={user.id} />
+}
+
+function BrainOnboardingContent() {
 	const router = useRouter()
 	const params = useSearchParams()
 	const queryClient = useQueryClient()
@@ -122,33 +141,67 @@ export default function BrainOnboardingPage() {
 		visibility: "team-private",
 		suggestChanges: false,
 	})
+	const [hydratedDraftUserId, setHydratedDraftUserId] = useState<string | null>(
+		null,
+	)
 
 	useEffect(() => {
-		if (forceCreate) return
-		try {
-			const raw = localStorage.getItem(STORAGE_KEY)
-			if (!raw) return
-			const cached = JSON.parse(raw) as {
-				mode?: BrainMode
-				about?: AboutValues
-				sources?: SourcesValues
-				team?: TeamValues
-			}
-			if (cached.mode && !modeParam) setMode(cached.mode)
-			if (cached.about) setAbout((a) => ({ ...a, ...cached.about }))
-			if (cached.sources) setSources((s) => ({ ...s, ...cached.sources }))
-			if (cached.team) setTeam((t) => ({ ...t, ...cached.team }))
-		} catch {}
-	}, [forceCreate, modeParam])
+		const userId = user?.id
+		if (!userId) {
+			setHydratedDraftUserId(null)
+			return
+		}
+
+		const storage = getOnboardingDraftStorage()
+		if (storage) discardLegacyOnboardingDraft(storage)
+		const cached =
+			forceCreate || !storage
+				? null
+				: readOnboardingDraft<BrainOnboardingDraft>(storage, userId)
+
+		setMode(cached?.mode && !modeParam ? cached.mode : detectedMode)
+		setAbout({
+			name: user.name ?? "",
+			about: "",
+			workspaceName: nameParam || suggestedWorkspaceName,
+			workspaceDomain: domain ?? "",
+			...cached?.about,
+		})
+		setSources({
+			connected: {},
+			driveScope: "selective",
+			...cached?.sources,
+		})
+		setTeam({
+			invites: [],
+			visibility: "team-private",
+			suggestChanges: false,
+			...cached?.team,
+		})
+		setHydratedDraftUserId(userId)
+	}, [
+		user?.id,
+		user?.name,
+		forceCreate,
+		modeParam,
+		detectedMode,
+		nameParam,
+		suggestedWorkspaceName,
+		domain,
+	])
 
 	useEffect(() => {
-		try {
-			localStorage.setItem(
-				STORAGE_KEY,
-				JSON.stringify({ mode, about, sources, team }),
-			)
-		} catch {}
-	}, [mode, about, sources, team])
+		const userId = user?.id
+		if (!userId || hydratedDraftUserId !== userId) return
+		const storage = getOnboardingDraftStorage()
+		if (!storage) return
+		writeOnboardingDraft(storage, userId, {
+			mode,
+			about,
+			sources,
+			team,
+		})
+	}, [user?.id, hydratedDraftUserId, mode, about, sources, team])
 
 	const navTrigger = useRef<"user" | "auto">("auto")
 	const startedRef = useRef(false)
@@ -226,16 +279,18 @@ export default function BrainOnboardingPage() {
 			).length,
 			invites_sent: team.invites.filter((i) => i.email.trim()).length,
 		})
-		try {
-			localStorage.removeItem(STORAGE_KEY)
-		} catch {}
+		const storage = getOnboardingDraftStorage()
+		if (storage) {
+			if (user?.id) clearOnboardingDraft(storage, user.id)
+			discardLegacyOnboardingDraft(storage)
+		}
 		// Extra org from settings: hard-reload so org-scoped caches don't show the previous org's data.
 		if (forcedCreateRef.current) {
 			window.location.href = "/?onboarded=1"
 			return
 		}
 		router.push("/?onboarded=1")
-	}, [router, mode, sources, team])
+	}, [router, mode, sources, team, user?.id])
 
 	const goNext = useCallback(() => {
 		const idx = steps.indexOf(step)
diff --git a/apps/web/lib/brain-onboarding-draft.test.ts b/apps/web/lib/brain-onboarding-draft.test.ts
new file mode 100644
index 00000000..e0567608
--- /dev/null
+++ b/apps/web/lib/brain-onboarding-draft.test.ts
@@ -0,0 +1,95 @@
+import { describe, expect, test } from "bun:test"
+import {
+	clearOnboardingDraft,
+	discardLegacyOnboardingDraft,
+	getOnboardingDraftStorage,
+	onboardingDraftKey,
+	readOnboardingDraft,
+	writeOnboardingDraft,
+} from "./brain-onboarding-draft"
+
+function createStorage() {
+	const values = new Map<string, string>()
+	return {
+		getItem: (key: string) => values.get(key) ?? null,
+		setItem: (key: string, value: string) => values.set(key, value),
+		removeItem: (key: string) => values.delete(key),
+		values,
+	}
+}
+
+describe("brain onboarding draft storage", () => {
+	test("isolates drafts belonging to different users", () => {
+		const storage = createStorage()
+		const accountADraft = {
+			about: { workspaceName: "Account A workspace" },
+			team: { invites: [{ email: "private-a@example.com" }] },
+		}
+
+		writeOnboardingDraft(storage, "account-a", accountADraft)
+
+		expect(readOnboardingDraft(storage, "account-a")).toEqual(accountADraft)
+		expect(readOnboardingDraft(storage, "account-b")).toBeNull()
+		expect(onboardingDraftKey("account-a")).not.toBe(
+			onboardingDraftKey("account-b"),
+		)
+		expect(onboardingDraftKey("account/a")).toBe(
+			"supermemory-brain-onboarding-v2:account%2Fa",
+		)
+	})
+
+	test("clears only the current user's draft", () => {
+		const storage = createStorage()
+		writeOnboardingDraft(storage, "account-a", { mode: "team" })
+		writeOnboardingDraft(storage, "account-b", { mode: "personal" })
+
+		clearOnboardingDraft(storage, "account-a")
+
+		expect(readOnboardingDraft(storage, "account-a")).toBeNull()
+		expect(readOnboardingDraft(storage, "account-b")).toEqual({
+			mode: "personal",
+		})
+	})
+
+	test("discards unattributable legacy drafts without migrating them", () => {
+		const storage = createStorage()
+		storage.setItem(
+			"supermemory-brain-onboarding-v1",
+			JSON.stringify({ about: { name: "Previous account" } }),
+		)
+
+		discardLegacyOnboardingDraft(storage)
+
+		expect(storage.getItem("supermemory-brain-onboarding-v1")).toBeNull()
+		expect(readOnboardingDraft(storage, "current-account")).toBeNull()
+	})
+
+	test("ignores corrupt and non-object drafts", () => {
+		const storage = createStorage()
+		storage.setItem(onboardingDraftKey("account-a"), "not-json")
+		storage.setItem(onboardingDraftKey("account-b"), "[]")
+
+		expect(readOnboardingDraft(storage, "account-a")).toBeNull()
+		expect(readOnboardingDraft(storage, "account-b")).toBeNull()
+	})
+
+	test("treats a blocked browser storage getter as unavailable", () => {
+		const original = Object.getOwnPropertyDescriptor(globalThis, "localStorage")
+		Object.defineProperty(globalThis, "localStorage", {
+			configurable: true,
+			get: () => {
+				throw new Error("blocked")
+			},
+		})
+
+		try {
+			expect(getOnboardingDraftStorage()).toBeNull()
+		} finally {
+			if (original) {
+				Object.defineProperty(globalThis, "localStorage", original)
+			} else {
+				Reflect.deleteProperty(globalThis, "localStorage")
+			}
+		}
+	})
+})
diff --git a/apps/web/lib/brain-onboarding-draft.ts b/apps/web/lib/brain-onboarding-draft.ts
new file mode 100644
index 00000000..2bbb4e84
--- /dev/null
+++ b/apps/web/lib/brain-onboarding-draft.ts
@@ -0,0 +1,65 @@
+const LEGACY_ONBOARDING_DRAFT_KEY = "supermemory-brain-onboarding-v1"
+const ONBOARDING_DRAFT_KEY_PREFIX = "supermemory-brain-onboarding-v2"
+
+export type OnboardingDraftStorage = Pick<
+	Storage,
+	"getItem" | "setItem" | "removeItem"
+>
+
+export function getOnboardingDraftStorage(): OnboardingDraftStorage | null {
+	try {
+		return globalThis.localStorage ?? null
+	} catch {
+		return null
+	}
+}
+
+export function onboardingDraftKey(userId: string): string {
+	return `${ONBOARDING_DRAFT_KEY_PREFIX}:${encodeURIComponent(userId)}`
+}
+
+export function readOnboardingDraft<T extends object>(
+	storage: OnboardingDraftStorage,
+	userId: string,
+): T | null {
+	try {
+		const raw = storage.getItem(onboardingDraftKey(userId))
+		if (!raw) return null
+		const parsed: unknown = JSON.parse(raw)
+		if (!parsed || typeof parsed !== "object" || Array.isArray(parsed)) {
+			return null
+		}
+		return parsed as T
+	} catch {
+		return null
+	}
+}
+
+export function writeOnboardingDraft(
+	storage: OnboardingDraftStorage,
+	userId: string,
+	draft: object,
+): void {
+	try {
+		storage.setItem(onboardingDraftKey(userId), JSON.stringify(draft))
+	} catch {}
+}
+
+export function clearOnboardingDraft(
+	storage: OnboardingDraftStorage,
+	userId: string,
+): void {
+	try {
+		storage.removeItem(onboardingDraftKey(userId))
+	} catch {}
+}
+
+// Legacy drafts cannot be attributed to an account safely. Discard them
+// instead of risking that the next signed-in user sees another user's data.
+export function discardLegacyOnboardingDraft(
+	storage: OnboardingDraftStorage,
+): void {
+	try {
+		storage.removeItem(LEGACY_ONBOARDING_DRAFT_KEY)
+	} catch {}
+}
diff --git a/apps/web/package.json b/apps/web/package.json
index 63c4acee..97152e9d 100644
--- a/apps/web/package.json
+++ b/apps/web/package.json
@@ -126,6 +126,7 @@
     "@types/node": "^24.0.4",
     "@types/react": "^19.2.9",
     "@types/react-dom": "^19.2.3",
+    "happy-dom": "^20.9.0",
     "tailwindcss": "^4.1.11",
     "typescript": "^5.8.3",
     "wrangler": "^4.26.0"