diff --git a/litellm/litellm_core_utils/request_timeout_resolver.py b/litellm/litellm_core_utils/request_timeout_resolver.py
index a32651fedee..0e011dc06a0 100644
--- a/litellm/litellm_core_utils/request_timeout_resolver.py
+++ b/litellm/litellm_core_utils/request_timeout_resolver.py
@@ -12,10 +12,15 @@ tell "user asked for this" from "nobody set it". This resolver answers that:
 
 from __future__ import annotations
 
-from typing import Final
+from collections.abc import Mapping
+from typing import Final, Literal, Protocol
+
+from pydantic import TypeAdapter
 
 from litellm.constants import DEFAULT_REQUEST_TIMEOUT_SECONDS
 
+_TIMEOUTS_BY_SERVICE_TIER: Final[TypeAdapter[Mapping[str, float] | None]] = TypeAdapter(Mapping[str, float] | None)
+
 
 def get_configured_request_timeout() -> float | None:
     """Return the explicitly-configured ``litellm.request_timeout``, else ``None``."""
@@ -27,3 +32,19 @@ def get_configured_request_timeout() -> float | None:
     if timeout != float(DEFAULT_REQUEST_TIMEOUT_SECONDS):
         return timeout
     return None
+
+
+class _DeploymentParams(Protocol):
+    def get(self, key: str, /) -> object: ...
+
+
+def get_service_tier_timeout(
+    service_tier: object,
+    litellm_params: _DeploymentParams,
+    key: Literal["timeout_by_service_tier", "stream_timeout_by_service_tier"],
+) -> float | None:
+    """Return the deployment's ``key`` timeout for the request's ``service_tier``, else ``None``."""
+    if not isinstance(service_tier, str):
+        return None
+    timeouts: Final = _TIMEOUTS_BY_SERVICE_TIER.validate_python(litellm_params.get(key))
+    return None if timeouts is None else timeouts.get(service_tier)
diff --git a/litellm/passthrough/timeout_utils.py b/litellm/passthrough/timeout_utils.py
index f600c7817f2..ce13552ff49 100644
--- a/litellm/passthrough/timeout_utils.py
+++ b/litellm/passthrough/timeout_utils.py
@@ -5,7 +5,10 @@ from typing import Final
 
 from pydantic import TypeAdapter
 
-from litellm.litellm_core_utils.request_timeout_resolver import get_configured_request_timeout
+from litellm.litellm_core_utils.request_timeout_resolver import (
+    get_configured_request_timeout,
+    get_service_tier_timeout,
+)
 
 DEFAULT_PASS_THROUGH_REQUEST_TIMEOUT_SECONDS: Final = 600.0
 
@@ -50,21 +53,27 @@ def resolve_llm_passthrough_timeout(
     Anthropic /v1/messages).
 
     Non-streaming precedence: kwargs timeout/request_timeout -> litellm_params
-    timeout/request_timeout -> router_timeout -> litellm.request_timeout (litellm_settings.request_timeout,
+    timeout_by_service_tier[kwargs service_tier] -> litellm_params timeout/request_timeout -> router_timeout -> litellm.request_timeout (litellm_settings.request_timeout,
     when explicitly set) -> general_settings.pass_through_request_timeout -> 600s default.
 
     Streaming (``kwargs["stream"]`` truthy) resolves ``stream_timeout`` at every level before
     any generic timeout, matching ``Router._get_stream_timeout`` on the completion route:
-    kwargs stream_timeout -> litellm_params stream_timeout -> router_stream_timeout, then the
-    non-streaming chain above.
+    kwargs stream_timeout -> litellm_params stream_timeout_by_service_tier[kwargs service_tier] ->
+    litellm_params stream_timeout -> router_stream_timeout, then the non-streaming chain above.
 
     Only the first set value is validated as seconds, so a value in a lower-precedence
     field never fails the call.
     """
     request: Final = kwargs if kwargs is not None else _NO_PARAMS
     deployment: Final = litellm_params if litellm_params is not None else _NO_PARAMS
+    service_tier: Final = request.get("service_tier")
     stream_candidates: Final = (
-        (request.get("stream_timeout"), deployment.get("stream_timeout"), router_stream_timeout)
+        (
+            request.get("stream_timeout"),
+            get_service_tier_timeout(service_tier, deployment, "stream_timeout_by_service_tier"),
+            deployment.get("stream_timeout"),
+            router_stream_timeout,
+        )
         if request.get("stream")
         else ()
     )
@@ -72,6 +81,7 @@ def resolve_llm_passthrough_timeout(
         *stream_candidates,
         request.get("timeout"),
         request.get("request_timeout"),
+        get_service_tier_timeout(service_tier, deployment, "timeout_by_service_tier"),
         deployment.get("timeout"),
         deployment.get("request_timeout"),
         router_timeout,
diff --git a/litellm/router.py b/litellm/router.py
index 7d1616fc967..14d7b582d77 100644
--- a/litellm/router.py
+++ b/litellm/router.py
@@ -111,6 +111,7 @@ from litellm.litellm_core_utils.ptu_pricing import (
 )
 from litellm.litellm_core_utils.request_timeout_resolver import (
     get_configured_request_timeout,
+    get_service_tier_timeout,
 )
 from litellm.litellm_core_utils.secret_redaction import redact_string
 from litellm.litellm_core_utils.sensitive_data_masker import (
@@ -4298,6 +4299,7 @@ class Router:
         """Helper to get stream timeout from kwargs or deployment params"""
         return (
             kwargs.get("stream_timeout", None)  # the params dynamically set by user
+            or get_service_tier_timeout(kwargs.get("service_tier"), data, "stream_timeout_by_service_tier")
             or data.get("stream_timeout", None)  # timeout set on litellm_params for this deployment
             or self.stream_timeout  # timeout set on router
             or self.request_timeout  # litellm_settings.request_timeout (per-attempt)
@@ -4309,6 +4311,7 @@ class Router:
         timeout: Final = (
             kwargs.get("timeout", None)  # the params dynamically set by user
             or kwargs.get("request_timeout", None)  # the params dynamically set by user
+            or get_service_tier_timeout(kwargs.get("service_tier"), data, "timeout_by_service_tier")
             or data.get("timeout", None)  # timeout set on litellm_params for this deployment
             or data.get("request_timeout", None)  # timeout set on litellm_params for this deployment
             or self.request_timeout  # litellm_settings.request_timeout (per-attempt)
diff --git a/litellm/types/litellm_params.py b/litellm/types/litellm_params.py
index 8b254cb4b67..6a446c704e3 100644
--- a/litellm/types/litellm_params.py
+++ b/litellm/types/litellm_params.py
@@ -76,6 +76,8 @@ class ProviderConnection:
     request_timeout: float | None = None
     force_timeout: float | None = None
     stream_timeout: float | str | None = None
+    timeout_by_service_tier: Mapping[str, float] | None = None
+    stream_timeout_by_service_tier: Mapping[str, float] | None = None
     max_retries: int | None = None
     tenant_id: str | None = None
     client_id: str | None = None
diff --git a/litellm/types/router.py b/litellm/types/router.py
index 67683e400ed..7cb15c0ddf5 100644
--- a/litellm/types/router.py
+++ b/litellm/types/router.py
@@ -471,6 +471,9 @@ class GenericLiteLLMParams(CredentialLiteLLMParams, CustomPricingLiteLLMParams):
     otpm: int | None = None
     timeout: float | str | httpx.Timeout | None = None  # if str, pass in as os.environ/
     stream_timeout: float | str | None = None  # timeout when making stream=True calls, if str, pass in as os.environ/
+    # per service_tier overrides of timeout / stream_timeout, used when the request's service_tier matches a key
+    timeout_by_service_tier: Mapping[str, float] | None = None
+    stream_timeout_by_service_tier: Mapping[str, float] | None = None
     max_retries: int | None = None
     drop_params: bool | str | None = None
     organization: str | None = None  # for openai orgs
@@ -659,6 +662,8 @@ class LiteLLMParamsTypedDict(TypedDict, total=False):
     api_version: str | None
     timeout: float | str | httpx.Timeout | None
     stream_timeout: float | str | None
+    timeout_by_service_tier: ReadOnly[Mapping[str, float] | None]
+    stream_timeout_by_service_tier: ReadOnly[Mapping[str, float] | None]
     max_retries: int | None
     organization: list | str | None  # for openai orgs
     provider_affinity_header: ReadOnly[str | None]
diff --git a/tests/unit/proxy/pass_through_endpoints/test_pass_through_endpoints.py b/tests/unit/proxy/pass_through_endpoints/test_pass_through_endpoints.py
index a6ce8ee6fbc..7be56cb9162 100644
--- a/tests/unit/proxy/pass_through_endpoints/test_pass_through_endpoints.py
+++ b/tests/unit/proxy/pass_through_endpoints/test_pass_through_endpoints.py
@@ -1318,6 +1318,32 @@ def test_resolve_llm_passthrough_timeout_validates_only_the_winning_value(
     assert resolve_llm_passthrough_timeout(kwargs=kwargs, litellm_params=litellm_params) == expected
 
 
+def test_resolve_llm_passthrough_timeout_uses_the_deployment_timeout_for_the_requests_service_tier():
+    litellm_params = {
+        "timeout": 610,
+        "stream_timeout": 30,
+        "timeout_by_service_tier": {"flex": 900},
+        "stream_timeout_by_service_tier": {"flex": 950},
+    }
+    assert resolve_llm_passthrough_timeout(kwargs={"service_tier": "flex"}, litellm_params=litellm_params) == 900.0
+    assert resolve_llm_passthrough_timeout(kwargs={"service_tier": "default"}, litellm_params=litellm_params) == 610.0
+    assert (
+        resolve_llm_passthrough_timeout(kwargs={"service_tier": "flex", "timeout": 20}, litellm_params=litellm_params)
+        == 20.0
+    )
+    assert (
+        resolve_llm_passthrough_timeout(kwargs={"service_tier": "flex", "stream": True}, litellm_params=litellm_params)
+        == 950.0
+    )
+    assert (
+        resolve_llm_passthrough_timeout(
+            kwargs={"service_tier": "flex", "stream": True},
+            litellm_params={"timeout": 610, "stream_timeout": 30, "timeout_by_service_tier": {"flex": 900}},
+        )
+        == 30.0
+    )
+
+
 def test_resolve_llm_passthrough_timeout_rejects_a_non_numeric_winner():
     with pytest.raises(ValidationError):
         resolve_llm_passthrough_timeout(kwargs={"timeout": httpx.Timeout(30.0)})
diff --git a/tests/unit/test_router/test_router_timeout.py b/tests/unit/test_router/test_router_timeout.py
index 8dd2684799e..e27f395beb2 100644
--- a/tests/unit/test_router/test_router_timeout.py
+++ b/tests/unit/test_router/test_router_timeout.py
@@ -132,3 +132,59 @@ def test_unit_test_streaming_timeout(stream):
         assert stream_timeout_val == stream_timeout
     else:
         assert stream_timeout_val == normal_timeout
+
+
+@pytest.mark.parametrize(
+    "request_kwargs, expected_timeout",
+    [
+        ({"service_tier": "flex"}, 900.0),
+        ({"service_tier": "default"}, 610.0),
+        ({}, 610.0),
+        ({"service_tier": "flex", "timeout": 20}, 20),
+        ({"service_tier": "flex", "stream": True}, 950.0),
+        ({"service_tier": "default", "stream": True}, 610.0),
+        ({"service_tier": "flex", "stream": True, "stream_timeout": 30}, 30),
+    ],
+)
+def test_the_deployment_timeout_for_the_requests_service_tier_wins_over_its_general_timeout(
+    request_kwargs: dict[str, object], expected_timeout: float
+) -> None:
+    router: Final = Router(
+        model_list=[
+            {
+                "model_name": "openai-gpt-5.1",
+                "litellm_params": {
+                    "model": "openai/gpt-5.1",
+                    "api_key": "sk-test",
+                    "timeout": 610,
+                    "stream_timeout": 610,
+                    "timeout_by_service_tier": {"flex": 900},
+                    "stream_timeout_by_service_tier": {"flex": 950},
+                },
+            }
+        ]
+    )
+    deployment_params: Final = router.model_list[0]["litellm_params"]
+
+    assert router._get_timeout(kwargs=request_kwargs, data=deployment_params) == expected_timeout
+
+
+def test_a_stream_keeps_the_deployment_stream_timeout_when_only_the_request_timeout_map_names_its_tier() -> None:
+    router: Final = Router(
+        model_list=[
+            {
+                "model_name": "openai-gpt-5.1",
+                "litellm_params": {
+                    "model": "openai/gpt-5.1",
+                    "api_key": "sk-test",
+                    "timeout": 610,
+                    "stream_timeout": 30,
+                    "timeout_by_service_tier": {"flex": 900},
+                },
+            }
+        ]
+    )
+    deployment_params: Final = router.model_list[0]["litellm_params"]
+
+    assert router._get_timeout(kwargs={"service_tier": "flex", "stream": True}, data=deployment_params) == 30.0
+    assert router._get_timeout(kwargs={"service_tier": "flex"}, data=deployment_params) == 900.0
diff --git a/tests/unit/types/test_litellm_params.py b/tests/unit/types/test_litellm_params.py
index f8e2befe237..fd3832a5748 100644
--- a/tests/unit/types/test_litellm_params.py
+++ b/tests/unit/types/test_litellm_params.py
@@ -74,6 +74,8 @@ CONNECTION_NAMES: Final = (
     "request_timeout",
     "force_timeout",
     "stream_timeout",
+    "timeout_by_service_tier",
+    "stream_timeout_by_service_tier",
     "max_retries",
     "tenant_id",
     "client_id",
diff --git a/ui/litellm-dashboard/src/lib/http/schema.d.ts b/ui/litellm-dashboard/src/lib/http/schema.d.ts
index 1fdf5776b1f..45131014f9b 100644
--- a/ui/litellm-dashboard/src/lib/http/schema.d.ts
+++ b/ui/litellm-dashboard/src/lib/http/schema.d.ts
@@ -36450,6 +36450,10 @@ export interface components {
             } | null;
             /** Stream Timeout */
             stream_timeout?: number | string | null;
+            /** Stream Timeout By Service Tier */
+            stream_timeout_by_service_tier?: {
+                [key: string]: number;
+            } | null;
             /** Tag Regex */
             tag_regex?: string[] | null;
             /** Tags */
@@ -36462,6 +36466,10 @@ export interface components {
             }[] | null;
             /** Timeout */
             timeout?: number | string | null;
+            /** Timeout By Service Tier */
+            timeout_by_service_tier?: {
+                [key: string]: number;
+            } | null;
             /** Tpm */
             tpm?: number | null;
             /** Use Chat Completions Api */
@@ -51875,6 +51883,10 @@ export interface components {
             } | null;
             /** Stream Timeout */
             stream_timeout?: number | string | null;
+            /** Stream Timeout By Service Tier */
+            stream_timeout_by_service_tier?: {
+                [key: string]: number;
+            } | null;
             /** Tag Regex */
             tag_regex?: string[] | null;
             /** Tags */
@@ -51887,6 +51899,10 @@ export interface components {
             }[] | null;
             /** Timeout */
             timeout?: number | string | null;
+            /** Timeout By Service Tier */
+            timeout_by_service_tier?: {
+                [key: string]: number;
+            } | null;
             /** Tpm */
             tpm?: number | null;
             /** Use Chat Completions Api */