diff --git a/apps/kitchensink-react/src/App.tsx b/apps/kitchensink-react/src/App.tsx
index 3cef4e7f..3e3ae34e 100644
--- a/apps/kitchensink-react/src/App.tsx
+++ b/apps/kitchensink-react/src/App.tsx
@@ -9,6 +9,10 @@ import {AppRoutes} from './AppRoutes'
 const theme = buildTheme({})
 
 const sanityConfigs: SanityConfig[] = [
+  {
+    projectId: 'project-id',
+    dataset: 'data-set',
+  },
   {
     projectId: 'ppsg7ml5',
     dataset: 'test',
diff --git a/packages/core/src/_exports/index.ts b/packages/core/src/_exports/index.ts
index da6371da..f75a120a 100644
--- a/packages/core/src/_exports/index.ts
+++ b/packages/core/src/_exports/index.ts
@@ -19,7 +19,7 @@ export {
   type LoggedOutAuthState,
   type LoggingInAuthState,
 } from '../auth/authStore'
-export {observeOrganizationVerificationState} from '../auth/getOrganizationVerificationState'
+export {ConfigurationError} from '../auth/ConfigurationError'
 export {handleAuthCallback} from '../auth/handleAuthCallback'
 export {logout} from '../auth/logout'
 export type {ClientStoreState as ClientState} from '../client/clientStore'
diff --git a/packages/react/src/components/auth/ConfigurationError.ts b/packages/core/src/auth/ConfigurationError.ts
similarity index 100%
rename from packages/react/src/components/auth/ConfigurationError.ts
rename to packages/core/src/auth/ConfigurationError.ts
diff --git a/packages/core/src/auth/authStore.ts b/packages/core/src/auth/authStore.ts
index ca0080a4..f95a003c 100644
--- a/packages/core/src/auth/authStore.ts
+++ b/packages/core/src/auth/authStore.ts
@@ -1,12 +1,15 @@
 import {type ClientConfig, createClient, type SanityClient} from '@sanity/client'
 import {type CurrentUser} from '@sanity/types'
-import {type Subscription} from 'rxjs'
+import {combineLatest, filter, map, type Subscription, switchMap} from 'rxjs'
 
 import {type AuthConfig, type AuthProvider} from '../config/authConfig'
 import {bindActionGlobally} from '../store/createActionBinder'
+import {type SanityInstance} from '../store/createSanityInstance'
 import {createStateSourceAction} from '../store/createStateSourceAction'
-import {defineStore} from '../store/defineStore'
+import {defineStore, type StoreContext} from '../store/defineStore'
+import {DEFAULT_API_VERSION, REQUEST_TAG_PREFIX} from './authConstants'
 import {AuthStateType} from './authStateType'
+import {ConfigurationError} from './ConfigurationError'
 import {refreshStampedToken} from './refreshStampedToken'
 import {checkForCookieAuth, getStudioTokenFromLocalStorage} from './studioModeAuth'
 import {subscribeToStateAndFetchCurrentUser} from './subscribeToStateAndFetchCurrentUser'
@@ -89,6 +92,7 @@ export interface AuthStoreState {
     authMethod: AuthMethodOptions
   }
   dashboardContext?: DashboardContext
+  error?: unknown
 }
 
 export const authStore = defineStore<AuthStoreState>({
@@ -211,6 +215,7 @@ export const authStore = defineStore<AuthStoreState>({
   initialize(context) {
     const subscriptions: Subscription[] = []
     subscriptions.push(subscribeToStateAndFetchCurrentUser(context))
+    subscriptions.push(listenToProjectIdsAndDashboard(context))
 
     if (context.state.get().options?.storageArea) {
       subscriptions.push(subscribeToStorageEventsAndSetToken(context))
@@ -229,6 +234,77 @@ export const authStore = defineStore<AuthStoreState>({
   },
 })
 
+function getProjectIdsFromInstanceAndParents(instance: SanityInstance | undefined): string[] {
+  if (!instance) return []
+
+  const projectIds: string[] = []
+  if (instance.config?.projectId) {
+    projectIds.push(instance.config.projectId)
+  }
+
+  const parentProjectIds = getProjectIdsFromInstanceAndParents(instance.getParent())
+  return projectIds.concat(parentProjectIds)
+}
+
+const listenToProjectIdsAndDashboard = ({instance, state}: StoreContext<AuthStoreState>) => {
+  const {
+    options: {clientFactory, apiHost},
+  } = state.get()
+
+  const projectIds = getProjectIdsFromInstanceAndParents(instance)
+
+  const token$ = state.observable.pipe(
+    map((i) => i.authState.type === AuthStateType.LOGGED_IN && i.authState.token),
+    filter((i) => typeof i === 'string'),
+  )
+
+  const client$ = token$.pipe(
+    map((token) =>
+      clientFactory({
+        apiVersion: DEFAULT_API_VERSION,
+        requestTagPrefix: REQUEST_TAG_PREFIX,
+        useProjectHostname: false,
+        useCdn: false,
+        token,
+        ...(apiHost && {apiHost}),
+      }),
+    ),
+  )
+
+  const orgId$ = state.observable.pipe(
+    map((i) => i.dashboardContext?.orgId),
+    filter(Boolean),
+  )
+
+  const organizationIdsFromProjects$ = combineLatest(
+    projectIds.map((projectId) =>
+      client$.pipe(
+        switchMap((client) => client.observable.projects.getById(projectId)),
+        map((i) => ({projectId: i.id, organizationId: i.organizationId})),
+      ),
+    ),
+  )
+
+  return combineLatest([orgId$, organizationIdsFromProjects$])
+    .pipe(
+      map(([orgId, orgIdsFromProjects]) => {
+        for (const {organizationId, projectId} of orgIdsFromProjects) {
+          if (orgId !== organizationId) {
+            throw new ConfigurationError(
+              new Error(
+                `Project ${projectId} is not part of organization ${orgId}. ` +
+                  `The project belongs to organization ${organizationId} instead.`,
+              ),
+            )
+          }
+        }
+      }),
+    )
+    .subscribe({
+      error: (error) => state.set('setError', {authState: {error, type: AuthStateType.ERROR}}),
+    })
+}
+
 /**
  * @public
  */
@@ -270,7 +346,10 @@ export const getLoginUrlState = bindActionGlobally(
  */
 export const getAuthState = bindActionGlobally(
   authStore,
-  createStateSourceAction(({state: {authState}}) => authState),
+  createStateSourceAction(({state: {authState}}) => {
+    if (authState.type === AuthStateType.ERROR) throw authState.error
+    return authState
+  }),
 )
 
 /**
diff --git a/packages/core/src/auth/getOrganizationVerificationState.test.ts b/packages/core/src/auth/getOrganizationVerificationState.test.ts
deleted file mode 100644
index 1fc020b5..00000000
--- a/packages/core/src/auth/getOrganizationVerificationState.test.ts
+++ /dev/null
@@ -1,197 +0,0 @@
-import {type Observable} from 'rxjs'
-import {TestScheduler} from 'rxjs/testing'
-import {beforeEach, describe, expect, it, vi} from 'vitest'
-
-import {
-  compareProjectOrganization,
-  type OrgVerificationResult,
-} from '../project/organizationVerification'
-import {getProjectState} from '../project/project'
-import {type SanityInstance} from '../store/createSanityInstance'
-import {type StateSource} from '../store/createStateSourceAction'
-import {getDashboardOrganizationId} from './dashboardUtils'
-import {observeOrganizationVerificationState} from './getOrganizationVerificationState'
-
-// Mock dependencies
-vi.mock('./dashboardUtils', () => ({
-  getDashboardOrganizationId: vi.fn(),
-}))
-vi.mock('../project/project', () => ({
-  getProjectState: vi.fn(),
-}))
-// Mock the comparison function to check its inputs
-vi.mock('../project/organizationVerification', async (importOriginal) => {
-  // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  const original = await importOriginal<any>()
-  return {
-    ...original,
-    compareProjectOrganization: vi.fn(),
-  }
-})
-
-describe('observeOrganizationVerificationState', () => {
-  let testScheduler: TestScheduler
-
-  // Mock instance (only config.projectId is used)
-  const mockInstance = {
-    config: {projectId: 'proj-1', dataset: 'd'},
-  } as SanityInstance
-
-  beforeEach(() => {
-    testScheduler = new TestScheduler((actual, expected) => {
-      expect(actual).toEqual(expected)
-    })
-    vi.clearAllMocks()
-  })
-
-  // Helper to mock getDashboardOrganizationId
-  const mockDashboardOrgId = (observable: Observable<string | null | undefined>) => {
-    vi.mocked(getDashboardOrganizationId).mockReturnValue({
-      observable,
-      getCurrent: () => undefined,
-      subscribe: observable.subscribe.bind(observable),
-      // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    } as any) // Cast to any to bypass strict type checking in mock
-  }
-
-  // Helper to mock getProjectState
-  const mockProjectOrgId = (observable: Observable<{organizationId: string | null} | null>) => {
-    vi.mocked(getProjectState).mockReturnValue({
-      // eslint-disable-next-line @typescript-eslint/no-explicit-any
-      observable: observable as any, // Cast needed due to complex type
-      // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    } as StateSource<any>)
-  }
-
-  // Helper to mock compareProjectOrganization result
-  const mockComparisonResult = (result: OrgVerificationResult) => {
-    vi.mocked(compareProjectOrganization).mockReturnValue(result)
-  }
-
-  it('should emit {error: null} if dashboardOrgId is null', () => {
-    testScheduler.run(({hot, expectObservable}) => {
-      const dashboardOrgId$ = hot('-a-', {a: null})
-      const projectOrgId$ = hot('--b', {b: {organizationId: 'org-real'}})
-
-      mockDashboardOrgId(dashboardOrgId$)
-      mockProjectOrgId(projectOrgId$)
-
-      const expectedMarble = '--a' // Corrected: combineLatest emits at frame 2
-      const expectedValues = {a: {error: null}}
-
-      const result$ = observeOrganizationVerificationState(mockInstance, [
-        mockInstance.config.projectId!,
-      ])
-      expectObservable(result$).toBe(expectedMarble, expectedValues)
-    })
-    expect(compareProjectOrganization).not.toHaveBeenCalled()
-  })
-
-  it('should emit {error: null} if instance.config.projectId is missing', () => {
-    const instanceWithoutProjectId = {
-      config: {projectId: undefined, dataset: 'd'},
-      // Add other required properties if SanityInstance type needs them
-    } as SanityInstance
-
-    testScheduler.run(({hot, expectObservable}) => {
-      // Dashboard org ID doesn't matter much here, but provide one
-      const dashboardOrgId$ = hot('-a-', {a: 'org-dash'})
-      // Project state fetch won't happen due to early return
-      const projectOrgId$: Observable<{organizationId: string | null} | null> = hot('--')
-
-      mockDashboardOrgId(dashboardOrgId$)
-      mockProjectOrgId(projectOrgId$)
-
-      // Should emit immediately (or based on dashboardOrgId$) due to missing projId
-      const expectedMarble = '-a' // Corrected: Emit at frame 1
-      const expectedValues = {a: {error: null}}
-
-      const result$ = observeOrganizationVerificationState(instanceWithoutProjectId, [])
-      expectObservable(result$).toBe(expectedMarble, expectedValues)
-    })
-    // No project fetch or comparison should occur
-    expect(getProjectState).not.toHaveBeenCalled()
-    expect(compareProjectOrganization).not.toHaveBeenCalled()
-  })
-
-  it('should emit an error if project fetch returns null when dashboard orgId is present', () => {
-    const comparisonError = {
-      error:
-        'Project proj-1 belongs to Organization unknown, but the Dashboard has Organization org-dash selected',
-    }
-
-    testScheduler.run(({hot, expectObservable}) => {
-      const dashboardOrgId$ = hot('-a-', {a: 'org-dash'})
-      const projectOrgId$ = hot('---n', {n: null}) // Project fetch returns null
-
-      mockDashboardOrgId(dashboardOrgId$)
-      mockProjectOrgId(projectOrgId$)
-      // Mock the result specifically for this test's inputs
-      vi.mocked(compareProjectOrganization).mockImplementation((pId, projOrgId, dashOrgId) => {
-        if (pId === 'proj-1' && projOrgId === null && dashOrgId === 'org-dash') {
-          return comparisonError
-        }
-        return {error: 'Unexpected call to compareProjectOrganization'} // Fail test if called unexpectedly
-      })
-
-      // When project fetch returns null, orgId becomes null, and the comparison is skipped.
-      const expectedMarble = '---r' // Should emit { error: null }
-      const expectedValues = {r: {error: null}} // Expect null error
-
-      const result$ = observeOrganizationVerificationState(mockInstance, [
-        mockInstance.config.projectId!,
-      ])
-      expectObservable(result$).toBe(expectedMarble, expectedValues)
-    })
-    // Comparison should NOT be called because projectData.orgId is null
-    expect(compareProjectOrganization).not.toHaveBeenCalled()
-    // Reset mock for other tests
-    vi.mocked(compareProjectOrganization).mockReset()
-  })
-
-  it('should call compareProjectOrganization and emit its result when IDs match', () => {
-    testScheduler.run(({hot, expectObservable}) => {
-      const dashboardOrgId$ = hot('-a-', {a: 'org-match'})
-      const projectOrgId$ = hot('--b', {b: {organizationId: 'org-match'}})
-      const comparisonResult = {error: null}
-
-      mockDashboardOrgId(dashboardOrgId$)
-      mockProjectOrgId(projectOrgId$)
-      mockComparisonResult(comparisonResult)
-
-      const expectedMarble = '--r' // Emits when projectOrgId$ emits
-      const expectedValues = {r: comparisonResult}
-
-      const result$ = observeOrganizationVerificationState(mockInstance, [
-        mockInstance.config.projectId!,
-      ])
-      expectObservable(result$).toBe(expectedMarble, expectedValues)
-    })
-
-    // Check that comparison was called with correct values after observables emit
-    expect(compareProjectOrganization).toHaveBeenCalledTimes(1)
-    expect(compareProjectOrganization).toHaveBeenCalledWith('proj-1', 'org-match', 'org-match')
-  })
-
-  it('should call compareProjectOrganization and emit its result when IDs mismatch', () => {
-    testScheduler.run(({hot, expectObservable}) => {
-      const dashboardOrgId$ = hot('-a-', {a: 'org-dash'})
-      const projectOrgId$ = hot('--b', {b: {organizationId: 'org-proj'}})
-      const comparisonResult = {error: 'Mismatch detected'}
-
-      mockDashboardOrgId(dashboardOrgId$)
-      mockProjectOrgId(projectOrgId$)
-      mockComparisonResult(comparisonResult)
-
-      const expectedMarble = '--r'
-      const expectedValues = {r: comparisonResult}
-
-      const result$ = observeOrganizationVerificationState(mockInstance, [
-        mockInstance.config.projectId!,
-      ])
-      expectObservable(result$).toBe(expectedMarble, expectedValues)
-    })
-    expect(compareProjectOrganization).toHaveBeenCalledTimes(1)
-    expect(compareProjectOrganization).toHaveBeenCalledWith('proj-1', 'org-proj', 'org-dash')
-  })
-})
diff --git a/packages/core/src/auth/getOrganizationVerificationState.ts b/packages/core/src/auth/getOrganizationVerificationState.ts
deleted file mode 100644
index faf2e5c4..00000000
--- a/packages/core/src/auth/getOrganizationVerificationState.ts
+++ /dev/null
@@ -1,73 +0,0 @@
-import {combineLatest, distinctUntilChanged, map, type Observable, of, switchMap} from 'rxjs'
-
-import {
-  compareProjectOrganization,
-  type OrgVerificationResult,
-} from '../project/organizationVerification'
-import {getProjectState} from '../project/project'
-import {type SanityInstance} from '../store/createSanityInstance'
-import {getDashboardOrganizationId} from './dashboardUtils'
-
-/**
- * Creates an observable that emits the organization verification state for a given instance.
- * It combines the dashboard organization ID (from auth context) with the
- * project's actual organization ID (fetched via getProjectState) and compares them.
- * @public
- */
-export function observeOrganizationVerificationState(
-  instance: SanityInstance,
-  projectIds: string[],
-): Observable<OrgVerificationResult> {
-  // Observable for the dashboard org ID (potentially null)
-  const dashboardOrgId$ =
-    getDashboardOrganizationId(instance).observable.pipe(distinctUntilChanged())
-
-  // Create observables for each project's org ID
-  const projectOrgIdObservables = projectIds.map((id) =>
-    getProjectState(instance, {projectId: id}).observable.pipe(
-      map((project) => ({projectId: id, orgId: project?.organizationId ?? null})),
-      // Ensure we only proceed if the orgId is loaded, distinct prevents unnecessary checks
-      distinctUntilChanged((prev, curr) => prev.orgId === curr.orgId),
-    ),
-  )
-
-  // Combine observables to get all project org IDs
-  const allProjectOrgIds$ =
-    projectOrgIdObservables.length > 0 ? combineLatest(projectOrgIdObservables) : of([])
-
-  // Combine the sources
-  return combineLatest([dashboardOrgId$, allProjectOrgIds$]).pipe(
-    switchMap(([dashboardOrgId, projectOrgDataArray]) => {
-      // If no dashboard org ID is set, or no project IDs provided, verification isn't applicable/possible
-      if (!dashboardOrgId || projectOrgDataArray.length === 0) {
-        return of<OrgVerificationResult>({error: null}) // Return success (no error)
-      }
-
-      // Iterate through all projects and check organization IDs
-      for (const projectData of projectOrgDataArray) {
-        // If a project doesn't have an orgId, we can't verify, treat as non-blocking for now
-        // (Matches original logic where null projectOrgId resulted in {error: null})
-        if (!projectData.orgId) {
-          continue
-        }
-
-        // Perform the comparison for the current project
-        const result = compareProjectOrganization(
-          projectData.projectId,
-          projectData.orgId,
-          dashboardOrgId,
-        )
-
-        // If any project fails verification, immediately return the error
-        if (result.error) {
-          return of(result)
-        }
-      }
-
-      // If all projects passed verification (or had no orgId to check)
-      return of<OrgVerificationResult>({error: null})
-    }),
-    // Only emit when the overall error status actually changes
-    distinctUntilChanged((prev, curr) => prev.error === curr.error),
-  )
-}
diff --git a/packages/core/src/project/project.ts b/packages/core/src/project/project.ts
index a553794c..b2740f68 100644
--- a/packages/core/src/project/project.ts
+++ b/packages/core/src/project/project.ts
@@ -1,5 +1,6 @@
-import {switchMap} from 'rxjs'
+import {catchError, switchMap} from 'rxjs'
 
+import {ConfigurationError} from '../auth/ConfigurationError'
 import {getClientState} from '../client/clientStore'
 import {type ProjectHandle} from '../config/sanityConfig'
 import {createFetcherStore} from '../utils/createFetcherStore'
@@ -11,7 +12,7 @@ const project = createFetcherStore({
   getKey: (instance, options?: ProjectHandle) => {
     const projectId = options?.projectId ?? instance.config.projectId
     if (!projectId) {
-      throw new Error('A projectId is required to use the project API.')
+      throw new ConfigurationError(new Error('A projectId is required to use the project API.'))
     }
     return projectId
   },
@@ -31,6 +32,9 @@ const project = createFetcherStore({
             (projectId ?? instance.config.projectId)!,
           ),
         ),
+        catchError((error) => {
+          throw new ConfigurationError(error)
+        }),
       )
     },
 })
diff --git a/packages/react/src/_exports/sdk-react.ts b/packages/react/src/_exports/sdk-react.ts
index 0fa82995..5ae7712d 100644
--- a/packages/react/src/_exports/sdk-react.ts
+++ b/packages/react/src/_exports/sdk-react.ts
@@ -12,7 +12,6 @@ export {useDashboardOrganizationId} from '../hooks/auth/useDashboardOrganization
 export {useHandleAuthCallback} from '../hooks/auth/useHandleAuthCallback'
 export {useLoginUrl} from '../hooks/auth/useLoginUrl'
 export {useLogOut} from '../hooks/auth/useLogOut'
-export {useVerifyOrgProjects} from '../hooks/auth/useVerifyOrgProjects'
 export {useClient} from '../hooks/client/useClient'
 export {
   type FrameConnection,
diff --git a/packages/react/src/components/SDKError.tsx b/packages/react/src/components/SDKError.tsx
new file mode 100644
index 00000000..53767329
--- /dev/null
+++ b/packages/react/src/components/SDKError.tsx
@@ -0,0 +1,28 @@
+import {ConfigurationError} from '@sanity/sdk'
+import {type FallbackProps} from 'react-error-boundary'
+
+/**
+ * @alpha
+ */
+export type SDKErrorProps = FallbackProps
+
+/**
+ * Displays authentication error details and provides retry functionality.
+ * Only handles {@link ClientError} instances - rethrows other error types.
+ *
+ * @alpha
+ */
+export function SDKError({error}: SDKErrorProps): React.ReactNode {
+  if (!(error instanceof ConfigurationError)) {
+    throw error
+  }
+
+  return (
+    <div className="sc-login-error">
+      <div className="sc-login-error__content">
+        <h2 className="sc-login-error__title">Configuration Error</h2>
+        <p className="sc-login-error__description">{error.message}</p>
+      </div>
+    </div>
+  )
+}
diff --git a/packages/react/src/components/auth/AuthBoundary.test.tsx b/packages/react/src/components/auth/AuthBoundary.test.tsx
index 86bb883d..1b774294 100644
--- a/packages/react/src/components/auth/AuthBoundary.test.tsx
+++ b/packages/react/src/components/auth/AuthBoundary.test.tsx
@@ -7,7 +7,6 @@ import {beforeEach, describe, expect, it, type MockInstance, vi} from 'vitest'
 import {ResourceProvider} from '../../context/ResourceProvider'
 import {useAuthState} from '../../hooks/auth/useAuthState'
 import {useLoginUrl} from '../../hooks/auth/useLoginUrl'
-import {useVerifyOrgProjects} from '../../hooks/auth/useVerifyOrgProjects'
 import {AuthBoundary} from './AuthBoundary'
 
 // Mock hooks
@@ -104,7 +103,6 @@ describe('AuthBoundary', () => {
   let consoleErrorSpy: MockInstance
   const mockUseAuthState = vi.mocked(useAuthState)
   const mockUseLoginUrl = vi.mocked(useLoginUrl)
-  const mockUseVerifyOrgProjects = vi.mocked(useVerifyOrgProjects)
   const testProjectIds = ['proj-test'] // Example project ID for tests
 
   beforeEach(() => {
@@ -114,8 +112,6 @@ describe('AuthBoundary', () => {
     // eslint-disable-next-line @typescript-eslint/no-explicit-any
     mockUseAuthState.mockReturnValue({type: AuthStateType.LOGGED_IN} as any)
     mockUseLoginUrl.mockReturnValue('http://example.com/login')
-    // Default mock for useVerifyOrgProjects - returns null (no error)
-    mockUseVerifyOrgProjects.mockImplementation(() => null)
   })
 
   afterEach(() => {
@@ -129,7 +125,7 @@ describe('AuthBoundary', () => {
     })
     render(
       <ResourceProvider fallback={null}>
-        <AuthBoundary projectIds={testProjectIds}>Protected Content</AuthBoundary>
+        <AuthBoundary>Protected Content</AuthBoundary>
       </ResourceProvider>,
     )
 
@@ -146,7 +142,7 @@ describe('AuthBoundary', () => {
     })
     const {container} = render(
       <ResourceProvider fallback={null}>
-        <AuthBoundary projectIds={testProjectIds}>Protected Content</AuthBoundary>
+        <AuthBoundary>Protected Content</AuthBoundary>
       </ResourceProvider>,
     )
 
@@ -163,7 +159,7 @@ describe('AuthBoundary', () => {
     })
     render(
       <ResourceProvider fallback={null}>
-        <AuthBoundary projectIds={testProjectIds}>Protected Content</AuthBoundary>
+        <AuthBoundary>Protected Content</AuthBoundary>
       </ResourceProvider>,
     )
 
@@ -177,7 +173,7 @@ describe('AuthBoundary', () => {
     })
     render(
       <ResourceProvider fallback={null}>
-        <AuthBoundary projectIds={testProjectIds}>Protected Content</AuthBoundary>
+        <AuthBoundary>Protected Content</AuthBoundary>
       </ResourceProvider>,
     )
 
@@ -194,7 +190,7 @@ describe('AuthBoundary', () => {
   it('renders children when logged in and org verification passes', () => {
     render(
       <ResourceProvider fallback={null}>
-        <AuthBoundary projectIds={testProjectIds}>Protected Content</AuthBoundary>
+        <AuthBoundary>Protected Content</AuthBoundary>
       </ResourceProvider>,
     )
     expect(screen.getByText('Protected Content')).toBeInTheDocument()
@@ -204,18 +200,10 @@ describe('AuthBoundary', () => {
     const orgErrorMessage = 'Organization mismatch!'
     // eslint-disable-next-line @typescript-eslint/no-explicit-any
     mockUseAuthState.mockReturnValue({type: AuthStateType.LOGGED_IN} as any)
-    // Mock specific return value for this test
-    mockUseVerifyOrgProjects.mockImplementation((disabled, pIds) => {
-      // Expect verification to be enabled (disabled=false) and projectIds to match
-      if (!disabled && pIds === testProjectIds) {
-        return orgErrorMessage
-      }
-      return null // Default case
-    })
 
     // Need to catch the error thrown during render. ErrorBoundary mock handles this.
     render(
-      <AuthBoundary verifyOrganization={true} projectIds={testProjectIds}>
+      <AuthBoundary>
         <div>Protected Content</div>
       </AuthBoundary>,
     )
@@ -245,7 +233,7 @@ describe('AuthBoundary', () => {
     })
 
     render(
-      <AuthBoundary verifyOrganization={false} projectIds={testProjectIds}>
+      <AuthBoundary>
         <div>Protected Content</div>
       </AuthBoundary>,
     )
@@ -264,11 +252,9 @@ describe('AuthBoundary', () => {
       error: new Error(authErrorMessage),
       // eslint-disable-next-line @typescript-eslint/no-explicit-any
     } as any)
-    mockUseVerifyOrgProjects.mockReturnValue(null) // Org verification passes or is irrelevant
-    mockUseVerifyOrgProjects.mockImplementation(() => null)
 
     render(
-      <AuthBoundary projectIds={testProjectIds}>
+      <AuthBoundary>
         <div>Protected Content</div>
       </AuthBoundary>,
     )
diff --git a/packages/react/src/components/auth/AuthBoundary.tsx b/packages/react/src/components/auth/AuthBoundary.tsx
index d439e28b..55b563bd 100644
--- a/packages/react/src/components/auth/AuthBoundary.tsx
+++ b/packages/react/src/components/auth/AuthBoundary.tsx
@@ -4,10 +4,8 @@ import {ErrorBoundary, type FallbackProps} from 'react-error-boundary'
 
 import {useAuthState} from '../../hooks/auth/useAuthState'
 import {useLoginUrl} from '../../hooks/auth/useLoginUrl'
-import {useVerifyOrgProjects} from '../../hooks/auth/useVerifyOrgProjects'
 import {isInIframe} from '../utils'
 import {AuthError} from './AuthError'
-import {ConfigurationError} from './ConfigurationError'
 import {LoginCallback} from './LoginCallback'
 import {LoginError, type LoginErrorProps} from './LoginError'
 
@@ -58,25 +56,11 @@ export interface AuthBoundaryProps {
   /** Header content to display */
   header?: React.ReactNode
 
-  /**
-   * The project IDs to use for organization verification.
-   */
-  projectIds?: string[]
-
   /** Footer content to display */
   footer?: React.ReactNode
 
   /** Protected content to render when authenticated */
   children?: React.ReactNode
-
-  /**
-   * Whether to verify that the project belongs to the organization specified in the dashboard context.
-   * By default, organization verification is enabled when running in a dashboard context.
-   *
-   * WARNING: Disabling organization verification is NOT RECOMMENDED and may cause your application
-   * to break in the future. This should never be disabled in production environments.
-   */
-  verifyOrganization?: boolean
 }
 
 /**
@@ -129,19 +113,10 @@ interface AuthSwitchProps {
   header?: React.ReactNode
   footer?: React.ReactNode
   children?: React.ReactNode
-  verifyOrganization?: boolean
-  projectIds?: string[]
 }
 
-function AuthSwitch({
-  CallbackComponent = LoginCallback,
-  children,
-  verifyOrganization = true,
-  projectIds,
-  ...props
-}: AuthSwitchProps) {
+function AuthSwitch({CallbackComponent = LoginCallback, children, ...props}: AuthSwitchProps) {
   const authState = useAuthState()
-  const orgError = useVerifyOrgProjects(!verifyOrganization, projectIds)
 
   const isLoggedOut = authState.type === AuthStateType.LOGGED_OUT && !authState.isDestroyingSession
   const loginUrl = useLoginUrl()
@@ -153,11 +128,6 @@ function AuthSwitch({
     }
   }, [isLoggedOut, loginUrl])
 
-  // Only check the error if verification is enabled
-  if (verifyOrganization && orgError) {
-    throw new ConfigurationError({message: orgError})
-  }
-
   switch (authState.type) {
     case AuthStateType.ERROR: {
       throw new AuthError(authState.error)
diff --git a/packages/react/src/components/auth/LoginError.tsx b/packages/react/src/components/auth/LoginError.tsx
index 255d5160..e87e80ff 100644
--- a/packages/react/src/components/auth/LoginError.tsx
+++ b/packages/react/src/components/auth/LoginError.tsx
@@ -1,12 +1,9 @@
 import {ClientError} from '@sanity/client'
-import {AuthStateType} from '@sanity/sdk'
-import {useCallback, useEffect, useState} from 'react'
+import {useCallback, useEffect, useMemo} from 'react'
 import {type FallbackProps} from 'react-error-boundary'
 
-import {useAuthState} from '../../hooks/auth/useAuthState'
 import {useLogOut} from '../../hooks/auth/useLogOut'
-import {AuthError} from './AuthError'
-import {ConfigurationError} from './ConfigurationError'
+import {isAuthError} from '../utils'
 /**
  * @alpha
  */
@@ -19,13 +16,15 @@ export type LoginErrorProps = FallbackProps
  * @alpha
  */
 export function LoginError({error, resetErrorBoundary}: LoginErrorProps): React.ReactNode {
-  if (!(error instanceof AuthError || error instanceof ConfigurationError)) throw error
+  if (!(error instanceof ClientError)) {
+    throw error
+  }
+
   const logout = useLogOut()
-  const authState = useAuthState()
+  // const authState = useAuthState()
 
-  const [authErrorMessage, setAuthErrorMessage] = useState(
-    'Please try again or contact support if the problem persists.',
-  )
+  // const authErrorMessage = error.message
+  // const [authErrorMessage, setAuthErrorMessage] = useState(error.message)
 
   const handleRetry = useCallback(async () => {
     await logout()
@@ -33,29 +32,25 @@ export function LoginError({error, resetErrorBoundary}: LoginErrorProps): React.
   }, [logout, resetErrorBoundary])
 
   useEffect(() => {
-    if (authState.type === AuthStateType.ERROR && authState.error instanceof ClientError) {
-      if (authState.error.statusCode === 401) {
-        handleRetry()
-      } else if (authState.error.statusCode === 404) {
-        const errorMessage = authState.error.response.body.message || ''
-        if (errorMessage.startsWith('Session with sid') && errorMessage.endsWith('not found')) {
-          setAuthErrorMessage('The session ID is invalid or expired.')
-        } else {
-          setAuthErrorMessage('The login link is invalid or expired. Please try again.')
-        }
-      }
+    const needsRetry = error instanceof ClientError && isAuthError(error)
+    if (needsRetry) {
+      handleRetry()
     }
-    if (authState.type !== AuthStateType.ERROR && error instanceof ConfigurationError) {
-      setAuthErrorMessage(error.message)
+  }, [error, handleRetry])
+
+  const authErrorMessage = useMemo(() => {
+    const errMess = error.response.body.message || ''
+    if (errMess.startsWith('Session with sid') && errMess.endsWith('not found')) {
+      return 'The session ID is invalid or expired.'
+    } else {
+      return errMess
     }
-  }, [authState, handleRetry, error])
+  }, [error])
 
   return (
     <div className="sc-login-error">
       <div className="sc-login-error__content">
-        <h2 className="sc-login-error__title">
-          {error instanceof AuthError ? 'Authentication Error' : 'Configuration Error'}
-        </h2>
+        <h2 className="sc-login-error__title">Authentication Error</h2>
         <p className="sc-login-error__description">{authErrorMessage}</p>
       </div>
 
diff --git a/packages/react/src/components/utils.ts b/packages/react/src/components/utils.ts
index 7a3b1fa1..d49bd108 100644
--- a/packages/react/src/components/utils.ts
+++ b/packages/react/src/components/utils.ts
@@ -1,3 +1,5 @@
+import {type ClientError} from '@sanity/client'
+
 export function isInIframe(): boolean {
   return typeof window !== 'undefined' && window.self !== window.top
 }
@@ -20,3 +22,27 @@ export function isLocalUrl(window: Window): boolean {
     url.startsWith('https://127.0.0.1')
   )
 }
+
+/**
+ * @internal
+ *
+ * Checks if the ClientError is an authentication error that requires a logout.
+ *
+ * @param error - The ClientError to check
+ * @returns True if the error is an authentication error that requires a logout, false otherwise
+ */
+export function isAuthError(error: ClientError): boolean {
+  const SANITY_AUTH_ERROR_CODES = [
+    'SIO-401-ANF', // The token specified is not valid or has been deleted
+    'SIO-401-AWH', // The token specified does not belong to the configured project
+    'SIO-401-AEX', // The token is expired
+  ] as const
+  if (error.statusCode !== 401) {
+    return false
+  }
+  const errorCode = error.response.body.errorCode
+  if (!errorCode) {
+    return false
+  }
+  return SANITY_AUTH_ERROR_CODES.includes(errorCode)
+}
diff --git a/packages/react/src/context/ResourceProvider.tsx b/packages/react/src/context/ResourceProvider.tsx
index 3fe0d663..23c5b26b 100644
--- a/packages/react/src/context/ResourceProvider.tsx
+++ b/packages/react/src/context/ResourceProvider.tsx
@@ -1,6 +1,8 @@
 import {createSanityInstance, type SanityConfig, type SanityInstance} from '@sanity/sdk'
 import {Suspense, useContext, useEffect, useMemo, useRef} from 'react'
+import {ErrorBoundary, type FallbackProps} from 'react-error-boundary'
 
+import {SDKError} from '../components/SDKError'
 import {SanityInstanceContext} from './SanityInstanceContext'
 
 const DEFAULT_FALLBACK = (
@@ -20,6 +22,7 @@ export interface ResourceProviderProps extends SanityConfig {
    */
   fallback: React.ReactNode
   children: React.ReactNode
+  ErrorComponent?: React.ComponentType<FallbackProps>
 }
 
 /**
@@ -70,6 +73,7 @@ export interface ResourceProviderProps extends SanityConfig {
 export function ResourceProvider({
   children,
   fallback,
+  ErrorComponent = SDKError,
   ...config
 }: ResourceProviderProps): React.ReactNode {
   const parent = useContext(SanityInstanceContext)
@@ -105,7 +109,9 @@ export function ResourceProvider({
 
   return (
     <SanityInstanceContext.Provider value={instance}>
-      <Suspense fallback={fallback ?? DEFAULT_FALLBACK}>{children}</Suspense>
+      <ErrorBoundary FallbackComponent={ErrorComponent}>
+        <Suspense fallback={fallback ?? DEFAULT_FALLBACK}>{children}</Suspense>
+      </ErrorBoundary>
     </SanityInstanceContext.Provider>
   )
 }
diff --git a/packages/react/src/hooks/auth/useVerifyOrgProjects.test.tsx b/packages/react/src/hooks/auth/useVerifyOrgProjects.test.tsx
deleted file mode 100644
index fdb2d472..00000000
--- a/packages/react/src/hooks/auth/useVerifyOrgProjects.test.tsx
+++ /dev/null
@@ -1,136 +0,0 @@
-import {observeOrganizationVerificationState, type OrgVerificationResult} from '@sanity/sdk'
-import {act, renderHook, waitFor} from '@testing-library/react'
-import {Subject} from 'rxjs'
-import {describe, expect, it, vi} from 'vitest'
-
-import {useSanityInstance} from '../context/useSanityInstance'
-import {useVerifyOrgProjects} from './useVerifyOrgProjects'
-
-// Mock dependencies
-vi.mock('@sanity/sdk', async (importOriginal) => {
-  const original = await importOriginal<typeof import('@sanity/sdk')>()
-  return {
-    ...original,
-    observeOrganizationVerificationState: vi.fn(),
-  }
-})
-vi.mock('../context/useSanityInstance')
-
-describe('useVerifyOrgProjects', () => {
-  // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  const mockInstance = {config: {}} as any // Dummy instance
-  const mockObserve = vi.mocked(observeOrganizationVerificationState)
-  const mockUseInstance = vi.mocked(useSanityInstance)
-  const testProjectIds = ['proj-1']
-
-  beforeEach(() => {
-    vi.clearAllMocks()
-    mockUseInstance.mockReturnValue(mockInstance)
-  })
-
-  it('should return null and not observe state if disabled', () => {
-    const {result} = renderHook(() => useVerifyOrgProjects(true, testProjectIds))
-
-    expect(result.current).toBeNull()
-    expect(mockObserve).not.toHaveBeenCalled()
-  })
-
-  it('should return null and not observe state if projectIds is missing or empty', () => {
-    const {result: resultUndefined} = renderHook(() => useVerifyOrgProjects(false, undefined))
-    expect(resultUndefined.current).toBeNull()
-    expect(mockObserve).not.toHaveBeenCalled()
-
-    const {result: resultEmpty} = renderHook(() => useVerifyOrgProjects(false, []))
-    expect(resultEmpty.current).toBeNull()
-    expect(mockObserve).not.toHaveBeenCalled()
-  })
-
-  it('should return null initially when not disabled and projectIds provided', () => {
-    const subject = new Subject<OrgVerificationResult>()
-    mockObserve.mockReturnValue(subject.asObservable())
-
-    const {result} = renderHook(() => useVerifyOrgProjects(false, testProjectIds))
-
-    expect(result.current).toBeNull()
-    expect(mockObserve).toHaveBeenCalledWith(mockInstance, testProjectIds)
-  })
-
-  it('should return null if observable emits { error: null }', async () => {
-    const subject = new Subject<OrgVerificationResult>()
-    mockObserve.mockReturnValue(subject.asObservable())
-
-    const {result} = renderHook(() => useVerifyOrgProjects(false, testProjectIds))
-
-    act(() => {
-      subject.next({error: null})
-    })
-
-    await waitFor(() => {
-      expect(result.current).toBeNull()
-    })
-  })
-
-  it('should return error string if observable emits { error: string }', async () => {
-    const subject = new Subject<OrgVerificationResult>()
-    const errorMessage = 'Org mismatch'
-    mockObserve.mockReturnValue(subject.asObservable())
-
-    const {result} = renderHook(() => useVerifyOrgProjects(false, testProjectIds))
-
-    act(() => {
-      subject.next({error: errorMessage})
-    })
-
-    await waitFor(() => {
-      expect(result.current).toBe(errorMessage)
-    })
-  })
-
-  it('should unsubscribe on unmount', () => {
-    const subject = new Subject<OrgVerificationResult>()
-    const unsubscribeSpy = vi.spyOn(subject, 'unsubscribe')
-    mockObserve.mockReturnValue(subject)
-
-    const {unmount} = renderHook(() => useVerifyOrgProjects(false, testProjectIds))
-
-    expect(unsubscribeSpy).not.toHaveBeenCalled()
-    unmount()
-    // Note: RxJS handles the inner subscription cleanup when the source (Subject) completes or errors,
-    // but testing library unmount should trigger the useEffect cleanup which calls unsubscribe.
-    // However, the spy might be on the Subject itself, not the final Subscription object.
-    // Let's adjust to spy on the returned subscription directly if possible, or accept this limitation.
-    // For now, we assume the useEffect cleanup calls unsubscribe correctly.
-    // We can validate subscription logic more deeply if needed.
-    // For this test, let's check if the observable reference still has observers.
-    expect(subject.observed).toBe(false) // Check if observers are gone after unmount
-  })
-
-  it('should clear the error if disabled becomes true', async () => {
-    const subject = new Subject<OrgVerificationResult>()
-    const errorMessage = 'Org mismatch'
-    mockObserve.mockReturnValue(subject.asObservable())
-
-    const {result, rerender} = renderHook(
-      ({disabled, pIds}) => useVerifyOrgProjects(disabled, pIds),
-      {
-        initialProps: {disabled: false, pIds: testProjectIds},
-      },
-    )
-
-    // Set initial error
-    act(() => {
-      subject.next({error: errorMessage})
-    })
-    await waitFor(() => {
-      expect(result.current).toBe(errorMessage)
-    })
-
-    // Disable the hook
-    rerender({disabled: true, pIds: testProjectIds})
-
-    // Error should be cleared
-    await waitFor(() => {
-      expect(result.current).toBeNull()
-    })
-  })
-})
diff --git a/packages/react/src/hooks/auth/useVerifyOrgProjects.tsx b/packages/react/src/hooks/auth/useVerifyOrgProjects.tsx
deleted file mode 100644
index 04c8d25c..00000000
--- a/packages/react/src/hooks/auth/useVerifyOrgProjects.tsx
+++ /dev/null
@@ -1,48 +0,0 @@
-import {observeOrganizationVerificationState, type OrgVerificationResult} from '@sanity/sdk'
-import {useEffect, useState} from 'react'
-
-import {useSanityInstance} from '../context/useSanityInstance'
-
-/**
- * Hook that verifies the current projects belongs to the organization ID specified in the dashboard context.
- *
- * @public
- * @param disabled - When true, disables verification and skips project verification API calls
- * @returns Error message if the project doesn't match the organization ID, or null if all match or verification isn't needed
- * @category Projects
- * @example
- * ```tsx
- * function OrgVerifier() {
- *   const error = useVerifyOrgProjects()
- *
- *   if (error) {
- *     return <div className="error">{error}</div>
- *   }
- *
- *   return <div>Organization projects verified!</div>
- * }
- * ```
- */
-export function useVerifyOrgProjects(disabled = false, projectIds?: string[]): string | null {
-  const instance = useSanityInstance()
-  const [error, setError] = useState<string | null>(null)
-
-  useEffect(() => {
-    if (disabled || !projectIds || projectIds.length === 0) {
-      if (error !== null) setError(null)
-      return
-    }
-
-    const verificationObservable$ = observeOrganizationVerificationState(instance, projectIds)
-
-    const subscription = verificationObservable$.subscribe((result: OrgVerificationResult) => {
-      setError(result.error)
-    })
-
-    return () => {
-      subscription.unsubscribe()
-    }
-  }, [instance, disabled, error, projectIds])
-
-  return error
-}