diff --git a/apps/sim/app/workspace/[workspaceId]/settings/components/byok/byok.tsx b/apps/sim/app/workspace/[workspaceId]/settings/components/byok/byok.tsx
index c365196abcd..d297cc49e3a 100644
--- a/apps/sim/app/workspace/[workspaceId]/settings/components/byok/byok.tsx
+++ b/apps/sim/app/workspace/[workspaceId]/settings/components/byok/byok.tsx
@@ -33,6 +33,7 @@ import {
   SerperIcon,
   TogetherIcon,
   WizaIcon,
+  xAIIcon,
   ZeroBounceIcon,
 } from '@/components/icons'
 import { MAX_BYOK_KEYS_PER_PROVIDER } from '@/lib/api/contracts/byok-keys'
@@ -75,6 +76,13 @@ const PROVIDERS: (BYOKManagerProvider & { id: BYOKProviderId })[] = [
     description: 'LLM calls and Knowledge Base OCR',
     placeholder: 'Enter your API key',
   },
+  {
+    id: 'xai',
+    name: 'xAI',
+    icon: xAIIcon,
+    description: 'LLM calls',
+    placeholder: 'xai-...',
+  },
   {
     id: 'fireworks',
     name: 'Fireworks',
@@ -279,6 +287,7 @@ const PROVIDER_SECTIONS: BYOKProviderSection[] = [
       'anthropic',
       'google',
       'mistral',
+      'xai',
       'fireworks',
       'together',
       'baseten',
diff --git a/apps/sim/executor/handlers/pi/keys.test.ts b/apps/sim/executor/handlers/pi/keys.test.ts
index 17b407cc0ad..17c45a6d6ef 100644
--- a/apps/sim/executor/handlers/pi/keys.test.ts
+++ b/apps/sim/executor/handlers/pi/keys.test.ts
@@ -134,6 +134,21 @@ describe('resolvePiModelKey', () => {
     expect(mockGetApiKeyWithBYOK).not.toHaveBeenCalled()
   })
 
+  it('cloud mode falls back to a stored workspace key for xAI', async () => {
+    mockGetProviderFromModel.mockReturnValue('xai')
+    mockGetBYOKKey.mockResolvedValue({ apiKey: 'xai-workspace-key', isBYOK: true })
+
+    const result = await resolvePiModelKey({
+      model: 'grok-4.5',
+      mode: 'cloud',
+      workspaceId: 'ws-1',
+    })
+
+    expect(result).toEqual({ providerId: 'xai', apiKey: 'xai-workspace-key', isBYOK: true })
+    expect(mockGetBYOKKey).toHaveBeenCalledWith('ws-1', 'xai')
+    expect(mockGetApiKeyWithBYOK).not.toHaveBeenCalled()
+  })
+
   it('cloud mode rejects when no user key is available (never a hosted key)', async () => {
     mockGetProviderFromModel.mockReturnValue('anthropic')
     mockGetBYOKKey.mockResolvedValue(null)
diff --git a/apps/sim/executor/handlers/pi/keys.ts b/apps/sim/executor/handlers/pi/keys.ts
index 9d85eb8a4ee..cc28d6de4b4 100644
--- a/apps/sim/executor/handlers/pi/keys.ts
+++ b/apps/sim/executor/handlers/pi/keys.ts
@@ -33,7 +33,13 @@ interface ResolvePiModelKeyParams {
 }
 
 /** Providers whose key Sim can store as a workspace BYOK key (read back for cloud). */
-const WORKSPACE_BYOK_PROVIDERS = new Set<string>(['anthropic', 'openai', 'google', 'mistral'])
+const WORKSPACE_BYOK_PROVIDERS = new Set<string>([
+  'anthropic',
+  'openai',
+  'google',
+  'mistral',
+  'xai',
+])
 
 /** Resolves the provider and a usable API key for the selected model. */
 export async function resolvePiModelKey(params: ResolvePiModelKeyParams): Promise<PiKeyResolution> {
diff --git a/apps/sim/lib/api-key/byok.ts b/apps/sim/lib/api-key/byok.ts
index 4a4f26b3271..6e45fe2cad8 100644
--- a/apps/sim/lib/api-key/byok.ts
+++ b/apps/sim/lib/api-key/byok.ts
@@ -205,13 +205,14 @@ export async function getApiKeyWithBYOK(
   const isGeminiModel = provider === 'google'
   const isMistralModel = provider === 'mistral'
   const isZaiModel = provider === 'zai'
+  const isXaiModel = provider === 'xai'
 
   const byokProviderId = isGeminiModel ? 'google' : (provider as BYOKProviderId)
 
   if (
     isHosted &&
     workspaceId &&
-    (isOpenAIModel || isClaudeModel || isGeminiModel || isMistralModel || isZaiModel)
+    (isOpenAIModel || isClaudeModel || isGeminiModel || isMistralModel || isZaiModel || isXaiModel)
   ) {
     const hostedModels = getHostedModels()
     const isModelHosted = hostedModels.some((m) => m.toLowerCase() === model.toLowerCase())
diff --git a/apps/sim/lib/api/contracts/byok-keys.ts b/apps/sim/lib/api/contracts/byok-keys.ts
index d9b8a561099..80e7b075df1 100644
--- a/apps/sim/lib/api/contracts/byok-keys.ts
+++ b/apps/sim/lib/api/contracts/byok-keys.ts
@@ -7,6 +7,7 @@ export const byokProviderIdSchema = z.enum([
   'google',
   'mistral',
   'zai',
+  'xai',
   'fireworks',
   'together',
   'baseten',
diff --git a/apps/sim/lib/core/config/api-keys.ts b/apps/sim/lib/core/config/api-keys.ts
index 1a1f04218cd..b435da46f22 100644
--- a/apps/sim/lib/core/config/api-keys.ts
+++ b/apps/sim/lib/core/config/api-keys.ts
@@ -12,7 +12,8 @@ export function getRotatingApiKey(provider: string): string {
     provider !== 'anthropic' &&
     provider !== 'gemini' &&
     provider !== 'cohere' &&
-    provider !== 'zai'
+    provider !== 'zai' &&
+    provider !== 'xai'
   ) {
     throw new Error(`No rotation implemented for provider: ${provider}`)
   }
@@ -39,6 +40,10 @@ export function getRotatingApiKey(provider: string): string {
     if (env.ZAI_API_KEY_1) keys.push(env.ZAI_API_KEY_1)
     if (env.ZAI_API_KEY_2) keys.push(env.ZAI_API_KEY_2)
     if (env.ZAI_API_KEY_3) keys.push(env.ZAI_API_KEY_3)
+  } else if (provider === 'xai') {
+    if (env.XAI_API_KEY_1) keys.push(env.XAI_API_KEY_1)
+    if (env.XAI_API_KEY_2) keys.push(env.XAI_API_KEY_2)
+    if (env.XAI_API_KEY_3) keys.push(env.XAI_API_KEY_3)
   }
 
   if (keys.length === 0) {
diff --git a/apps/sim/lib/core/config/env.ts b/apps/sim/lib/core/config/env.ts
index 6cf92e243a3..0be542a4f4c 100644
--- a/apps/sim/lib/core/config/env.ts
+++ b/apps/sim/lib/core/config/env.ts
@@ -147,6 +147,9 @@ export const env = createEnv({
     ZAI_API_KEY_1:                         z.string().min(1).optional(),           // Primary Z.ai API key for load balancing
     ZAI_API_KEY_2:                         z.string().min(1).optional(),           // Additional Z.ai API key for load balancing
     ZAI_API_KEY_3:                         z.string().min(1).optional(),           // Additional Z.ai API key for load balancing
+    XAI_API_KEY_1:                         z.string().min(1).optional(),           // Primary xAI API key for load balancing
+    XAI_API_KEY_2:                         z.string().min(1).optional(),           // Additional xAI API key for load balancing
+    XAI_API_KEY_3:                         z.string().min(1).optional(),           // Additional xAI API key for load balancing
     OLLAMA_URL:                            z.string().url().optional(),            // Ollama local LLM server URL
     VLLM_BASE_URL:                         z.string().url().optional(),            // vLLM self-hosted base URL (OpenAI-compatible)
     VLLM_API_KEY:                          z.string().optional(),                  // Optional bearer token for vLLM
diff --git a/apps/sim/lib/core/utils.test.ts b/apps/sim/lib/core/utils.test.ts
index a9e2b1662f9..7ccb5dc75cf 100644
--- a/apps/sim/lib/core/utils.test.ts
+++ b/apps/sim/lib/core/utils.test.ts
@@ -43,6 +43,9 @@ vi.mock('@/lib/core/config/env', () =>
     GEMINI_API_KEY_1: 'test-gemini-key-1',
     GEMINI_API_KEY_2: 'test-gemini-key-2',
     GEMINI_API_KEY_3: 'test-gemini-key-3',
+    XAI_API_KEY_1: 'test-xai-key-1',
+    XAI_API_KEY_2: 'test-xai-key-2',
+    XAI_API_KEY_3: 'test-xai-key-3',
   })
 )
 
@@ -327,6 +330,11 @@ describe('getRotatingApiKey', () => {
     expect(result).toMatch(/^test-gemini-key-[1-3]$/)
   })
 
+  it.concurrent('should return xAI API key based on current minute', () => {
+    const result = getRotatingApiKey('xai')
+    expect(result).toMatch(/^test-xai-key-[1-3]$/)
+  })
+
   it.concurrent('should throw error for unsupported provider', () => {
     expect(() => getRotatingApiKey('unsupported')).toThrow('No rotation implemented for provider')
   })
diff --git a/apps/sim/providers/models.test.ts b/apps/sim/providers/models.test.ts
index 0c01133649c..14dcee48590 100644
--- a/apps/sim/providers/models.test.ts
+++ b/apps/sim/providers/models.test.ts
@@ -218,3 +218,17 @@ describe('zai provider definition', () => {
     expect(getHostedModels()).toContain('glm-4.6')
   })
 })
+
+describe('xai provider definition', () => {
+  const xai = PROVIDER_DEFINITIONS.xai
+
+  it('is registered with grok-4.5 as the default model', () => {
+    expect(xai).toBeDefined()
+    expect(xai.id).toBe('xai')
+    expect(xai.defaultModel).toBe('grok-4.5')
+  })
+
+  it('is included in getHostedModels since Sim provides the xAI key server-side', () => {
+    expect(getHostedModels()).toContain('grok-4.5')
+  })
+})
diff --git a/apps/sim/providers/models.ts b/apps/sim/providers/models.ts
index e5021a4c721..bc5aa24cbe7 100644
--- a/apps/sim/providers/models.ts
+++ b/apps/sim/providers/models.ts
@@ -3921,6 +3921,7 @@ export function getHostedModels(): string[] {
     ...getProviderModels('anthropic'),
     ...getProviderModels('google'),
     ...getProviderModels('zai'),
+    ...getProviderModels('xai'),
   ]
 }
 
diff --git a/apps/sim/providers/utils.test.ts b/apps/sim/providers/utils.test.ts
index 1e9c877a976..1697c12f80d 100644
--- a/apps/sim/providers/utils.test.ts
+++ b/apps/sim/providers/utils.test.ts
@@ -865,7 +865,7 @@ describe('Cost Calculation', () => {
 })
 
 describe('getHostedModels', () => {
-  it.concurrent('should return OpenAI, Anthropic, and Google models as hosted', () => {
+  it.concurrent('should return OpenAI, Anthropic, Google, and xAI models as hosted', () => {
     const hostedModels = getHostedModels()
 
     expect(hostedModels).toContain('gpt-4o')
@@ -877,8 +877,9 @@ describe('getHostedModels', () => {
     expect(hostedModels).toContain('gemini-2.5-pro')
     expect(hostedModels).toContain('gemini-2.5-flash')
 
+    expect(hostedModels).toContain('grok-4.5')
+
     expect(hostedModels).not.toContain('deepseek-v3')
-    expect(hostedModels).not.toContain('grok-4-latest')
   })
 
   it.concurrent('should return an array of strings', () => {
@@ -902,11 +903,12 @@ describe('shouldBillModelUsage', () => {
 
     expect(shouldBillModelUsage('gemini-2.5-pro')).toBe(true)
     expect(shouldBillModelUsage('gemini-2.5-flash')).toBe(true)
+
+    expect(shouldBillModelUsage('grok-4.5')).toBe(true)
   })
 
   it.concurrent('should return false for non-hosted models', () => {
     expect(shouldBillModelUsage('deepseek-v3')).toBe(false)
-    expect(shouldBillModelUsage('grok-4-latest')).toBe(false)
 
     expect(shouldBillModelUsage('unknown-model')).toBe(false)
   })
diff --git a/apps/sim/providers/utils.ts b/apps/sim/providers/utils.ts
index 3b8bdd10c6a..8ca3017354a 100644
--- a/apps/sim/providers/utils.ts
+++ b/apps/sim/providers/utils.ts
@@ -903,8 +903,9 @@ export function getApiKey(provider: string, model: string, userProvidedKey?: str
   const isClaudeModel = provider === 'anthropic'
   const isGeminiModel = provider === 'google'
   const isZaiModel = provider === 'zai'
+  const isXaiModel = provider === 'xai'
 
-  if (isHosted && (isOpenAIModel || isClaudeModel || isGeminiModel || isZaiModel)) {
+  if (isHosted && (isOpenAIModel || isClaudeModel || isGeminiModel || isZaiModel || isXaiModel)) {
     const hostedModels = getHostedModels()
     const isModelHosted = hostedModels.some((m) => m.toLowerCase() === model.toLowerCase())
 
diff --git a/apps/sim/tools/types.ts b/apps/sim/tools/types.ts
index 910e825f251..cb3e7753a1d 100644
--- a/apps/sim/tools/types.ts
+++ b/apps/sim/tools/types.ts
@@ -8,6 +8,7 @@ export type BYOKProviderId =
   | 'google'
   | 'mistral'
   | 'zai'
+  | 'xai'
   | 'fireworks'
   | 'together'
   | 'baseten'