diff --git a/desktop/src/components/controls/ModelSelector.test.tsx b/desktop/src/components/controls/ModelSelector.test.tsx
index 59f9e0ea..78277703 100644
--- a/desktop/src/components/controls/ModelSelector.test.tsx
+++ b/desktop/src/components/controls/ModelSelector.test.tsx
@@ -1,9 +1,11 @@
-import { afterEach, describe, expect, it, vi } from 'vitest'
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
 import { act, cleanup, fireEvent, render, screen } from '@testing-library/react'
 import '@testing-library/jest-dom'
 
 import { ModelSelector } from './ModelSelector'
 import { useChatStore } from '../../stores/chatStore'
+import { useHahaOAuthStore } from '../../stores/hahaOAuthStore'
+import { useHahaOpenAIOAuthStore } from '../../stores/hahaOpenAIOAuthStore'
 import { useProviderStore } from '../../stores/providerStore'
 import { useSessionRuntimeStore } from '../../stores/sessionRuntimeStore'
 import { useSettingsStore } from '../../stores/settingsStore'
@@ -28,6 +30,14 @@ afterEach(() => {
   useProviderStore.setState(useProviderStore.getInitialState(), true)
   useSessionRuntimeStore.setState(useSessionRuntimeStore.getInitialState(), true)
   useChatStore.setState(useChatStore.getInitialState(), true)
+  useHahaOAuthStore.setState(useHahaOAuthStore.getInitialState(), true)
+  useHahaOpenAIOAuthStore.setState(useHahaOpenAIOAuthStore.getInitialState(), true)
+})
+
+// Prevent real API calls from fetchStatus on mount
+beforeEach(() => {
+  useHahaOAuthStore.setState({ fetchStatus: async () => {} })
+  useHahaOpenAIOAuthStore.setState({ fetchStatus: async () => {} })
 })
 
 describe('ModelSelector', () => {
@@ -135,6 +145,10 @@ describe('ModelSelector', () => {
       },
     ]
     const setSessionRuntime = vi.fn()
+    useHahaOpenAIOAuthStore.setState({
+      status: { loggedIn: true, expiresAt: null, email: null, accountId: null },
+      fetchStatus: async () => {},
+    })
     useSettingsStore.setState({
       locale: 'en',
       availableModels: openAIModels,
@@ -169,6 +183,45 @@ describe('ModelSelector', () => {
     })
   })
 
+  it('hides official provider sections when OAuth is not logged in', async () => {
+    useHahaOAuthStore.setState({ status: { loggedIn: false }, fetchStatus: async () => {} })
+    useHahaOpenAIOAuthStore.setState({ status: { loggedIn: false }, fetchStatus: async () => {} })
+    useSettingsStore.setState({
+      locale: 'en',
+      availableModels: MODELS,
+      currentModel: MODELS[0],
+      activeProviderName: 'Provider A',
+    })
+    useProviderStore.setState({
+      providers: [{
+        id: 'provider-a',
+        presetId: 'custom',
+        name: 'Provider A',
+        apiKey: '***',
+        baseUrl: 'https://api.example.com',
+        apiFormat: 'anthropic',
+        models: {
+          main: 'provider-main',
+          haiku: '',
+          sonnet: '',
+          opus: '',
+        },
+      }],
+      activeId: 'provider-a',
+      hasLoadedProviders: true,
+      isLoading: true,
+    })
+
+    render(<ModelSelector runtimeKey="session-hide" />)
+
+    await clickByRole(/alpha/i)
+
+    const dropdown = screen.getByTestId('model-selector-dropdown')
+    expect(dropdown.textContent).not.toContain('Claude Official')
+    expect(dropdown.textContent).not.toContain('ChatGPT Official')
+    expect(dropdown.textContent).toContain('Provider A')
+  })
+
   it('portals the dropdown outside clipping containers and positions it below the trigger', async () => {
     useSettingsStore.setState({
       locale: 'en',
diff --git a/desktop/src/components/controls/ModelSelector.tsx b/desktop/src/components/controls/ModelSelector.tsx
index b39ed9a7..45e651d2 100644
--- a/desktop/src/components/controls/ModelSelector.tsx
+++ b/desktop/src/components/controls/ModelSelector.tsx
@@ -16,6 +16,8 @@ import type { RuntimeSelection } from '../../types/runtime'
 import type { EffortLevel, ModelInfo } from '../../types/settings'
 import { useMobileViewport } from '../../hooks/useMobileViewport'
 import { isTauriRuntime } from '../../lib/desktopRuntime'
+import { useHahaOAuthStore } from '../../stores/hahaOAuthStore'
+import { useHahaOpenAIOAuthStore } from '../../stores/hahaOpenAIOAuthStore'
 import { MobileBottomSheet } from '../shared/MobileBottomSheet'
 
 type ProviderChoice = {
@@ -36,7 +38,8 @@ type Props = {
 }
 
 type DropdownPosition = {
-  top: number
+  top: number | undefined
+  bottom: number | undefined
   left: number
   width: number
   maxHeight: number
@@ -101,6 +104,8 @@ function buildProviderChoices(
   officialName: string,
   openAIOfficialName: string,
   labels: Record<'main' | 'haiku' | 'sonnet' | 'opus', string>,
+  claudeOfficialLoggedIn: boolean,
+  openAIOfficialLoggedIn: boolean,
 ): ProviderChoice[] {
   const claudeOfficialModels = activeId === null && availableModels.length > 0
     ? availableModels
@@ -109,21 +114,30 @@ function buildProviderChoices(
     ? availableModels
     : OPENAI_OFFICIAL_MODELS
 
-  return [
-    officialChoices(null, claudeOfficialModels, activeId === null, officialName),
-    officialChoices(
+  const choices: ProviderChoice[] = []
+
+  if (claudeOfficialLoggedIn) {
+    choices.push(officialChoices(null, claudeOfficialModels, activeId === null, officialName))
+  }
+  if (openAIOfficialLoggedIn) {
+    choices.push(officialChoices(
       OPENAI_OFFICIAL_PROVIDER_ID,
       openAIOfficialModels,
       activeId === OPENAI_OFFICIAL_PROVIDER_ID,
       openAIOfficialName,
-    ),
-    ...providers.map((provider) => ({
+    ))
+  }
+
+  for (const provider of providers) {
+    choices.push({
       providerId: provider.id,
       providerName: provider.name,
       isDefault: activeId === provider.id,
       models: buildProviderModels(provider, labels),
-    })),
-  ]
+    })
+  }
+
+  return choices
 }
 
 function resolveDefaultRuntimeSelection(
@@ -173,6 +187,10 @@ export function ModelSelector({
     isLoading: providersLoading,
     fetchProviders,
   } = useProviderStore()
+  const claudeOAuthStatus = useHahaOAuthStore((s) => s.status)
+  const fetchClaudeOAuthStatus = useHahaOAuthStore((s) => s.fetchStatus)
+  const openAIOAuthStatus = useHahaOpenAIOAuthStore((s) => s.status)
+  const fetchOpenAIOAuthStatus = useHahaOpenAIOAuthStore((s) => s.fetchStatus)
   const runtimeSelection = useSessionRuntimeStore((state) =>
     runtimeKey ? state.selections[runtimeKey] : undefined,
   )
@@ -200,6 +218,11 @@ export function ModelSelector({
     void fetchProviders()
   }, [fetchProviders, isRuntimeScoped, providersLoading])
 
+  useEffect(() => {
+    void fetchClaudeOAuthStatus()
+    void fetchOpenAIOAuthStatus()
+  }, [fetchClaudeOAuthStatus, fetchOpenAIOAuthStatus])
+
   useEffect(() => {
     if (!open) return
     const handleClick = (e: MouseEvent) => {
@@ -245,9 +268,8 @@ export function ModelSelector({
     const maxHeight = Math.min(DROPDOWN_MAX_HEIGHT, availableHeight)
 
     setDropdownPosition({
-      top: placeBelow
-        ? rect.bottom + DROPDOWN_GAP
-        : Math.max(VIEWPORT_MARGIN, rect.top - DROPDOWN_GAP - maxHeight),
+      top: placeBelow ? rect.bottom + DROPDOWN_GAP : undefined,
+      bottom: placeBelow ? undefined : (viewportHeight - rect.top + DROPDOWN_GAP),
       left,
       width,
       maxHeight,
@@ -290,8 +312,10 @@ export function ModelSelector({
       t('settings.providers.officialName'),
       t('settings.providers.openaiOfficialName'),
       roleLabels,
+      claudeOAuthStatus?.loggedIn === true,
+      openAIOAuthStatus?.loggedIn === true,
     ),
-    [activeId, availableModels, providers, roleLabels, t],
+    [activeId, availableModels, providers, roleLabels, t, claudeOAuthStatus, openAIOAuthStatus],
   )
 
   const selectedModel = isControlled
@@ -511,6 +535,7 @@ export function ModelSelector({
         className="fixed z-[80] rounded-xl border border-[var(--color-border)] bg-[var(--color-surface-container-lowest)] shadow-[var(--shadow-dropdown)]"
         style={{
           top: dropdownPosition.top,
+          bottom: dropdownPosition.bottom,
           left: dropdownPosition.left,
           width: dropdownPosition.width,
         }}