diff --git a/apps/sim/providers/utils.test.ts b/apps/sim/providers/utils.test.ts
index 7c30ac3c3a..ea8d7d5133 100644
--- a/apps/sim/providers/utils.test.ts
+++ b/apps/sim/providers/utils.test.ts
@@ -24,6 +24,7 @@ import {
   MODELS_WITH_VERBOSITY,
   PROVIDERS_WITH_TOOL_USAGE_CONTROL,
   prepareToolsWithUsageControl,
+  shouldBillModelUsage,
   supportsTemperature,
   supportsToolUsageControl,
   transformCustomTool,
@@ -40,6 +41,7 @@ describe('getApiKey', () => {
   beforeEach(() => {
     vi.clearAllMocks()
 
+    // @ts-expect-error - mocking boolean with different value
     isHostedSpy.mockReturnValue(false)
 
     module.require = vi.fn(() => ({
@@ -53,6 +55,7 @@ describe('getApiKey', () => {
   })
 
   it('should return user-provided key when not in hosted environment', () => {
+    // @ts-expect-error - mocking boolean with different value
     isHostedSpy.mockReturnValue(false)
 
     // For OpenAI
@@ -65,6 +68,7 @@ describe('getApiKey', () => {
   })
 
   it('should throw error if no key provided in non-hosted environment', () => {
+    // @ts-expect-error - mocking boolean with different value
     isHostedSpy.mockReturnValue(false)
 
     expect(() => getApiKey('openai', 'gpt-4')).toThrow('API key is required for openai gpt-4')
@@ -80,7 +84,8 @@ describe('getApiKey', () => {
       throw new Error('Rotation failed')
     })
 
-    const key = getApiKey('openai', 'gpt-4', 'user-fallback-key')
+    // Use gpt-4o which IS in the hosted models list
+    const key = getApiKey('openai', 'gpt-4o', 'user-fallback-key')
     expect(key).toBe('user-fallback-key')
   })
 
@@ -91,7 +96,8 @@ describe('getApiKey', () => {
       throw new Error('Rotation failed')
     })
 
-    expect(() => getApiKey('openai', 'gpt-4')).toThrow('No API key available for openai gpt-4')
+    // Use gpt-4o which IS in the hosted models list
+    expect(() => getApiKey('openai', 'gpt-4o')).toThrow('No API key available for openai gpt-4o')
   })
 
   it('should require user key for non-OpenAI/Anthropic providers even in hosted environment', () => {
@@ -104,6 +110,30 @@ describe('getApiKey', () => {
       'API key is required for other-provider some-model'
     )
   })
+
+  it('should require user key for models NOT in hosted list even if provider matches', () => {
+    isHostedSpy.mockReturnValue(true)
+
+    // Models with version suffixes that are NOT in the hosted list should require user API key
+    // even though they're from anthropic/openai providers
+
+    // User provides their own key - should work
+    const key1 = getApiKey('anthropic', 'claude-sonnet-4-20250514', 'user-key-anthropic')
+    expect(key1).toBe('user-key-anthropic')
+
+    // No user key - should throw, NOT use server key
+    expect(() => getApiKey('anthropic', 'claude-sonnet-4-20250514')).toThrow(
+      'API key is required for anthropic claude-sonnet-4-20250514'
+    )
+
+    // Same for OpenAI versioned models not in list
+    const key2 = getApiKey('openai', 'gpt-4o-2024-08-06', 'user-key-openai')
+    expect(key2).toBe('user-key-openai')
+
+    expect(() => getApiKey('openai', 'gpt-4o-2024-08-06')).toThrow(
+      'API key is required for openai gpt-4o-2024-08-06'
+    )
+  })
 })
 
 describe('Model Capabilities', () => {
@@ -476,6 +506,52 @@ describe('getHostedModels', () => {
   })
 })
 
+describe('shouldBillModelUsage', () => {
+  it.concurrent('should return true for exact matches of hosted models', () => {
+    // OpenAI models
+    expect(shouldBillModelUsage('gpt-4o')).toBe(true)
+    expect(shouldBillModelUsage('o1')).toBe(true)
+
+    // Anthropic models
+    expect(shouldBillModelUsage('claude-sonnet-4-0')).toBe(true)
+    expect(shouldBillModelUsage('claude-opus-4-0')).toBe(true)
+
+    // Google models
+    expect(shouldBillModelUsage('gemini-2.5-pro')).toBe(true)
+    expect(shouldBillModelUsage('gemini-2.5-flash')).toBe(true)
+  })
+
+  it.concurrent('should return false for non-hosted models', () => {
+    // Other providers
+    expect(shouldBillModelUsage('deepseek-v3')).toBe(false)
+    expect(shouldBillModelUsage('grok-4-latest')).toBe(false)
+
+    // Unknown models
+    expect(shouldBillModelUsage('unknown-model')).toBe(false)
+  })
+
+  it.concurrent('should return false for versioned model names not in hosted list', () => {
+    // Versioned model names that are NOT in the hosted list
+    // These should NOT be billed (user provides own API key)
+    expect(shouldBillModelUsage('claude-sonnet-4-20250514')).toBe(false)
+    expect(shouldBillModelUsage('gpt-4o-2024-08-06')).toBe(false)
+    expect(shouldBillModelUsage('claude-3-5-sonnet-20241022')).toBe(false)
+  })
+
+  it.concurrent('should be case insensitive', () => {
+    expect(shouldBillModelUsage('GPT-4O')).toBe(true)
+    expect(shouldBillModelUsage('Claude-Sonnet-4-0')).toBe(true)
+    expect(shouldBillModelUsage('GEMINI-2.5-PRO')).toBe(true)
+  })
+
+  it.concurrent('should not match partial model names', () => {
+    // Should not match partial/prefix models
+    expect(shouldBillModelUsage('gpt-4')).toBe(false) // gpt-4o is hosted, not gpt-4
+    expect(shouldBillModelUsage('claude-sonnet')).toBe(false)
+    expect(shouldBillModelUsage('gemini')).toBe(false)
+  })
+})
+
 describe('Provider Management', () => {
   describe('getProviderFromModel', () => {
     it.concurrent('should return correct provider for known models', () => {
diff --git a/apps/sim/providers/utils.ts b/apps/sim/providers/utils.ts
index 85718667a5..2a755c3095 100644
--- a/apps/sim/providers/utils.ts
+++ b/apps/sim/providers/utils.ts
@@ -619,7 +619,7 @@ export function getHostedModels(): string[] {
  */
 export function shouldBillModelUsage(model: string): boolean {
   const hostedModels = getHostedModels()
-  return hostedModels.includes(model)
+  return hostedModels.some((hostedModel) => model.toLowerCase() === hostedModel.toLowerCase())
 }
 
 /**
@@ -643,19 +643,22 @@ export function getApiKey(provider: string, model: string, userProvidedKey?: str
   const isGeminiModel = provider === 'google'
 
   if (isHosted && (isOpenAIModel || isClaudeModel || isGeminiModel)) {
-    try {
-      // Import the key rotation function
-      const { getRotatingApiKey } = require('@/lib/core/config/api-keys')
-      const serverKey = getRotatingApiKey(isGeminiModel ? 'gemini' : provider)
-      return serverKey
-    } catch (_error) {
-      // If server key fails and we have a user key, fallback to that
-      if (hasUserKey) {
-        return userProvidedKey!
-      }
+    // Only use server key if model is explicitly in our hosted list
+    const hostedModels = getHostedModels()
+    const isModelHosted = hostedModels.some((m) => m.toLowerCase() === model.toLowerCase())
+
+    if (isModelHosted) {
+      try {
+        const { getRotatingApiKey } = require('@/lib/core/config/api-keys')
+        const serverKey = getRotatingApiKey(isGeminiModel ? 'gemini' : provider)
+        return serverKey
+      } catch (_error) {
+        if (hasUserKey) {
+          return userProvidedKey!
+        }
 
-      // Otherwise, throw an error
-      throw new Error(`No API key available for ${provider} ${model}`)
+        throw new Error(`No API key available for ${provider} ${model}`)
+      }
     }
   }