diff --git a/src/resources/messages.ts b/src/resources/messages.ts
index 84d2f6bd..2bcd89a1 100644
--- a/src/resources/messages.ts
+++ b/src/resources/messages.ts
@@ -32,6 +32,13 @@ export class Messages extends APIResource {
     body: MessageCreateParams,
     options?: Core.RequestOptions,
   ): APIPromise<Message> | APIPromise<Stream<RawMessageStreamEvent>> {
+    if (body.model in DEPRECATED_MODELS) {
+      console.warn(
+        `The model '${body.model}' is deprecated and will reach end-of-life on ${
+          DEPRECATED_MODELS[body.model]
+        }\nPlease migrate to a newer model. Visit https://docs.anthropic.com/en/docs/resources/model-deprecations for more information.`,
+      );
+    }
     return this._client.post('/v1/messages', {
       body,
       timeout: (this._client as any)._options.timeout ?? 600000,
@@ -221,6 +228,18 @@ export type Model =
   | 'claude-2.0'
   | 'claude-instant-1.2';
 
+type DeprecatedModelsType = {
+  [K in Model]?: string;
+};
+
+const DEPRECATED_MODELS: DeprecatedModelsType = {
+  'claude-1.3': 'November 6th, 2024',
+  'claude-1.3-100k': 'November 6th, 2024',
+  'claude-instant-1.1': 'November 6th, 2024',
+  'claude-instant-1.1-100k': 'November 6th, 2024',
+  'claude-instant-1.2': 'November 6th, 2024',
+};
+
 export interface RawContentBlockDeltaEvent {
   delta: TextDelta | InputJSONDelta;
 
diff --git a/tests/api-resources/messages.test.ts b/tests/api-resources/messages.test.ts
index 99a74f80..5592a7c4 100644
--- a/tests/api-resources/messages.test.ts
+++ b/tests/api-resources/messages.test.ts
@@ -75,3 +75,34 @@ describe('resource messages', () => {
     });
   });
 });
+
+test('create: warns when using a deprecated model', async () => {
+  const consoleSpy = jest.spyOn(console, 'warn').mockImplementation();
+
+  await client.messages.create({
+    max_tokens: 1024,
+    messages: [{ content: 'Hello, world', role: 'user' }],
+    model: 'claude-instant-1.2',
+  });
+
+  expect(consoleSpy).toHaveBeenCalledWith(
+    "The model 'claude-instant-1.2' is deprecated and will reach end-of-life on November 6th, 2024\n" +
+      'Please migrate to a newer model. Visit https://docs.anthropic.com/en/docs/resources/model-deprecations for more information.',
+  );
+
+  consoleSpy.mockRestore();
+});
+
+test('create: does not warn for non-deprecated models', async () => {
+  const consoleSpy = jest.spyOn(console, 'warn').mockImplementation();
+
+  await client.messages.create({
+    max_tokens: 1024,
+    messages: [{ content: 'Hello, world', role: 'user' }],
+    model: 'claude-3-5-sonnet-20240620',
+  });
+
+  expect(consoleSpy).not.toHaveBeenCalled();
+
+  consoleSpy.mockRestore();
+});