diff --git a/aider/coders/base_coder.py b/aider/coders/base_coder.py
index 4c9f8eca9..7821ac202 100755
--- a/aider/coders/base_coder.py
+++ b/aider/coders/base_coder.py
@@ -589,7 +589,7 @@ class Coder:
 
     def send(self, messages, model=None, functions=None):
         if not model:
-            model = self.main_model.name
+            model = self.main_model
 
         self.partial_response_content = ""
         self.partial_response_function_call = dict()
diff --git a/aider/history.py b/aider/history.py
index d1ee70ede..9fdaf9c14 100644
--- a/aider/history.py
+++ b/aider/history.py
@@ -85,7 +85,7 @@ class ChatSummary:
             dict(role="user", content=content),
         ]
 
-        summary = simple_send_with_retries(self.client, self.model.name, messages)
+        summary = simple_send_with_retries(self.client, self.model, messages)
         if summary is None:
             raise ValueError(f"summarizer unexpectedly failed for {self.model.name}")
         summary = prompts.summary_prefix + summary
diff --git a/aider/main.py b/aider/main.py
index d4c8cb5c7..63ed0753d 100644
--- a/aider/main.py
+++ b/aider/main.py
@@ -189,7 +189,6 @@ def main(argv=None, input=None, output=None, force_git_root=None):
         metavar="OPENAI_API_VERSION",
         help="Specify the api_version",
     )
-    # TODO: use deployment_id
     model_group.add_argument(
         "--openai-api-deployment-id",
         metavar="OPENAI_API_DEPLOYMENT_ID",
@@ -507,7 +506,9 @@ def main(argv=None, input=None, output=None, force_git_root=None):
 
         client = openai.OpenAI(api_key=args.openai_api_key, **kwargs)
 
-    main_model = models.Model.create(args.model, client)
+    main_model = models.Model.create(
+        args.model, client, deployment_id=args.openai_api_deployment_id
+    )
 
     try:
         coder = Coder.create(
diff --git a/aider/models/model.py b/aider/models/model.py
index 70f09d313..7eb3be88c 100644
--- a/aider/models/model.py
+++ b/aider/models/model.py
@@ -16,13 +16,13 @@ class Model:
     completion_price = None
 
     @classmethod
-    def create(cls, name, client=None):
+    def create(cls, name, client=None, deployment_id=None):
         from .openai import OpenAIModel
         from .openrouter import OpenRouterModel
 
         if client and client.base_url.host == "openrouter.ai":
             return OpenRouterModel(client, name)
-        return OpenAIModel(name)
+        return OpenAIModel(name, deployment_id=deployment_id)
 
     def __str__(self):
         return self.name
diff --git a/aider/models/openai.py b/aider/models/openai.py
index 1c6286d63..435048868 100644
--- a/aider/models/openai.py
+++ b/aider/models/openai.py
@@ -13,8 +13,9 @@ known_tokens = {
 
 
 class OpenAIModel(Model):
-    def __init__(self, name):
+    def __init__(self, name, deployment_id=None):
         self.name = name
+        self.deployment_id = deployment_id
 
         tokens = None
 
diff --git a/aider/repo.py b/aider/repo.py
index 6943c5568..7fd096984 100644
--- a/aider/repo.py
+++ b/aider/repo.py
@@ -119,7 +119,7 @@ class GitRepo:
         ]
 
         for model in models.Model.commit_message_models():
-            commit_message = simple_send_with_retries(self.client, model.name, messages)
+            commit_message = simple_send_with_retries(self.client, model, messages)
             if commit_message:
                 break
 
diff --git a/aider/sendchat.py b/aider/sendchat.py
index c770ef087..baba6e682 100644
--- a/aider/sendchat.py
+++ b/aider/sendchat.py
@@ -28,10 +28,15 @@ CACHE = None
         f"{details.get('exception','Exception')}\nRetry in {details['wait']:.1f} seconds."
     ),
 )
-def send_with_retries(client, model_name, messages, functions, stream):
+def send_with_retries(client, model, messages, functions, stream):
     if not client:
         raise ValueError("No openai client provided")
 
+    if model.deployment_id:
+        model_name = model.deployment_id
+    else:
+        model_name = model.name
+
     kwargs = dict(
         model=model_name,
         messages=messages,
@@ -57,11 +62,11 @@ def send_with_retries(client, model_name, messages, functions, stream):
     return hash_object, res
 
 
-def simple_send_with_retries(client, model_name, messages):
+def simple_send_with_retries(client, model, messages):
     try:
         _hash, response = send_with_retries(
             client=client,
-            model_name=model_name,
+            model=model,
             messages=messages,
             functions=None,
             stream=False,
diff --git a/tests/test_sendchat.py b/tests/test_sendchat.py
index 7bb8fcfab..2613d1f3a 100644
--- a/tests/test_sendchat.py
+++ b/tests/test_sendchat.py
@@ -4,6 +4,7 @@ from unittest.mock import MagicMock, patch
 import httpx
 import openai
 
+from aider.models import Model
 from aider.sendchat import send_with_retries
 
 
@@ -27,7 +28,7 @@ class TestSendChat(unittest.TestCase):
         ]
 
         # Call the send_with_retries method
-        send_with_retries(mock_client, "model", ["message"], None, False)
+        send_with_retries(mock_client, Model.weak_model(), ["message"], None, False)
         mock_print.assert_called_once()
 
     @patch("aider.sendchat.openai.ChatCompletion.create")
@@ -42,5 +43,5 @@ class TestSendChat(unittest.TestCase):
         ]
 
         # Call the send_with_retries method
-        send_with_retries(mock_client, "model", ["message"], None, False)
+        send_with_retries(mock_client, Model.weak_model(), ["message"], None, False)
         mock_print.assert_called_once()