diff --git a/frontend/src/hooks/__tests__/useImport.test.ts b/frontend/src/hooks/__tests__/useImport.test.ts
new file mode 100644
index 00000000..07e3137d
--- /dev/null
+++ b/frontend/src/hooks/__tests__/useImport.test.ts
@@ -0,0 +1,93 @@
+import { renderHook, act, waitFor } from '@testing-library/react'
+import { vi, describe, it, expect, beforeEach } from 'vitest'
+import React from 'react'
+import { createTestQueryClient } from '../../test/createTestQueryClient'
+import { QueryClientProvider } from '@tanstack/react-query'
+
+import * as api from '../../api/import'
+import { useImport } from '../useImport'
+
+vi.mock('../../api/import', () => ({
+  uploadCaddyfile: vi.fn(),
+  getImportPreview: vi.fn(),
+  commitImport: vi.fn(),
+  getImportStatus: vi.fn(),
+  cancelImport: vi.fn(),
+}))
+
+const wrapper = ({ children }: { children: React.ReactNode }) => {
+  const qc = createTestQueryClient()
+  return React.createElement(QueryClientProvider, { client: qc }, children)
+}
+
+describe('useImport (unit)', () => {
+  beforeEach(() => vi.clearAllMocks())
+
+  it('commit throws when there is no active session (guards)', async () => {
+    vi.mocked(api.getImportStatus).mockResolvedValue({ has_pending: false })
+
+    const { result } = renderHook(() => useImport(), { wrapper })
+
+    await waitFor(() => expect(result.current.loading).toBe(false))
+
+    await expect(result.current.commit({}, {})).rejects.toThrow(/No active session/)
+  })
+
+  it('does not surface preview error when there is no pending session', async () => {
+    vi.mocked(api.getImportStatus).mockResolvedValue({ has_pending: false })
+    vi.mocked(api.getImportPreview).mockRejectedValue(new Error('preview fail'))
+
+    const { result } = renderHook(() => useImport(), { wrapper })
+
+    await waitFor(() => expect(result.current.loading).toBe(false))
+    // preview endpoint failed but there is no pending session => error should be null
+    expect(result.current.error).toBeNull()
+  })
+
+  it('surfaces preview error when session is pending and commit not succeeded', async () => {
+    vi.mocked(api.getImportStatus).mockResolvedValue({
+      has_pending: true,
+      session: { id: 's1', state: 'reviewing', created_at: '2026-01-31T00:00:00.000Z', updated_at: '2026-01-31T00:00:00.000Z' },
+    })
+    vi.mocked(api.getImportPreview).mockRejectedValue(new Error('preview fail'))
+
+    const { result } = renderHook(() => useImport(), { wrapper })
+
+    await waitFor(() => expect(result.current.loading).toBe(false))
+    expect(result.current.error).toContain('preview fail')
+  })
+
+  it('enables preview query when session state is pending', async () => {
+    const session = {
+      id: 's-pending',
+      state: 'pending' as const,
+      created_at: '2026-01-31T00:00:00.000Z',
+      updated_at: '2026-01-31T00:00:00.000Z',
+    }
+    vi.mocked(api.getImportStatus).mockResolvedValue({ has_pending: true, session })
+    vi.mocked(api.getImportPreview).mockResolvedValue({ session, preview: { hosts: [], conflicts: [], errors: [] } } as any)
+
+    const { result } = renderHook(() => useImport(), { wrapper })
+
+    await waitFor(() => expect(result.current.loading).toBe(false))
+    expect(api.getImportPreview).toHaveBeenCalled()
+  })
+
+  it('upload stores immediate uploadPreview and exposes preview', async () => {
+    const mockPreview = {
+      session: { id: 's1', state: 'reviewing', created_at: '2026-01-31T00:00:00.000Z', updated_at: '2026-01-31T00:00:00.000Z' },
+      preview: { hosts: [], conflicts: [], errors: [] },
+    }
+    vi.mocked(api.getImportStatus).mockResolvedValue({ has_pending: false })
+    vi.mocked(api.uploadCaddyfile).mockResolvedValue(mockPreview as any)
+
+    const { result } = renderHook(() => useImport(), { wrapper })
+
+    await act(async () => {
+      await result.current.upload('some content')
+    })
+
+    expect(api.uploadCaddyfile).toHaveBeenCalled()
+    expect(result.current.preview).toEqual(mockPreview)
+  })
+})