diff --git a/src/openai/lib/azure.py b/src/openai/lib/azure.py
index 27bebd8cab..310c337bf2 100644
--- a/src/openai/lib/azure.py
+++ b/src/openai/lib/azure.py
@@ -2,7 +2,7 @@
 
 import os
 import inspect
-from typing import Any, Union, Mapping, TypeVar, Callable, Awaitable, overload
+from typing import Any, Union, Mapping, TypeVar, Callable, Awaitable, overload, Optional
 from typing_extensions import Self, override
 
 import httpx
@@ -274,6 +274,21 @@ def _get_azure_ad_token(self) -> str | None:
 
         return None
 
+    @override
+    def _calculate_retry_timeout(
+        self,
+        remaining_retries: int,
+        options: FinalRequestOptions,
+        response_headers: Optional[httpx.Headers] = None,
+    ) -> float:
+        try:
+            if response_headers:
+                return float(response_headers["retry-after-ms"]) / 1000
+        except (KeyError, ValueError):
+            pass
+
+        return super()._calculate_retry_timeout(remaining_retries, options, response_headers)
+
     @override
     def _prepare_options(self, options: FinalRequestOptions) -> None:
         headers: dict[str, str | Omit] = {**options.headers} if is_given(options.headers) else {}
@@ -509,6 +524,21 @@ async def _get_azure_ad_token(self) -> str | None:
 
         return None
 
+    @override
+    def _calculate_retry_timeout(
+        self,
+        remaining_retries: int,
+        options: FinalRequestOptions,
+        response_headers: Optional[httpx.Headers] = None,
+    ) -> float:
+        try:
+            if response_headers:
+                return float(response_headers["retry-after-ms"]) / 1000
+        except (KeyError, ValueError):
+            pass
+
+        return super()._calculate_retry_timeout(remaining_retries, options, response_headers)
+
     @override
     async def _prepare_options(self, options: FinalRequestOptions) -> None:
         headers: dict[str, str | Omit] = {**options.headers} if is_given(options.headers) else {}
diff --git a/tests/lib/test_azure.py b/tests/lib/test_azure.py
index 9360b2925a..0da7447916 100644
--- a/tests/lib/test_azure.py
+++ b/tests/lib/test_azure.py
@@ -2,6 +2,7 @@
 from typing_extensions import Literal
 
 import pytest
+import httpx
 
 from openai._models import FinalRequestOptions
 from openai.lib.azure import AzureOpenAI, AsyncAzureOpenAI
@@ -64,3 +65,64 @@ def test_client_copying_override_options(client: Client) -> None:
         api_version="2022-05-01",
     )
     assert copied._custom_query == {"api-version": "2022-05-01"}
+
+
+@pytest.mark.parametrize(
+    "client,headers,timeout",
+    [
+        (sync_client, {"retry-after-ms": "2000"}, 2.0),
+        (sync_client, {"retry-after-ms": "2", "retry-after": "1"}, 0.002),
+        (sync_client, {"Retry-After-Ms": "2", "Retry-After": "1"}, 0.002),
+        (async_client, {"retry-after-ms": "2000"}, 2.0),
+        (async_client, {"retry-after-ms": "2", "retry-after": "1"}, 0.002),
+        (async_client, {"Retry-After-Ms": "2", "Retry-After": "1"}, 0.002),
+    ],
+)
+def test_parse_retry_after_ms_header(client: Client, headers: httpx.Headers, timeout: float) -> None:
+    headers = httpx.Headers(headers)
+    options = FinalRequestOptions(method="post", url="/completions")
+    retry_timeout = client._calculate_retry_timeout(
+        remaining_retries=2,
+        options=options,
+        response_headers=headers
+    )
+    assert retry_timeout == timeout
+
+
+@pytest.mark.parametrize(
+    "client,headers",
+    [
+        (sync_client, {}),
+        (async_client, {}),
+        (sync_client, None),
+        (async_client, None),
+    ],
+)
+def test_no_retry_after_header(client: Client, headers: httpx.Headers) -> None:
+    headers = httpx.Headers(headers)
+    options = FinalRequestOptions(method="post", url="/completions")
+    retry_timeout = client._calculate_retry_timeout(
+        remaining_retries=2,
+        options=options,
+        response_headers=headers
+    )
+    assert retry_timeout  # uses default retry implementation
+
+
+
+@pytest.mark.parametrize(
+    "client,headers",
+    [
+        (sync_client, {"retry-after-ms": "invalid"}),
+        (async_client, {"retry-after-ms": "invalid"}),
+    ],
+)
+def test_invalid_retry_after_header(client: Client, headers: httpx.Headers) -> None:
+    headers = httpx.Headers(headers)
+    options = FinalRequestOptions(method="post", url="/completions")
+    retry_timeout = client._calculate_retry_timeout(
+        remaining_retries=2,
+        options=options,
+        response_headers=headers
+    )
+    assert retry_timeout  # uses default retry implementation