diff --git a/seam/client.py b/seam/client.py
index 9965e905..b4c00c30 100644
--- a/seam/client.py
+++ b/seam/client.py
@@ -61,6 +61,9 @@ def _handle_error_response(self, response: requests.Response):
         if status_code == 401:
             raise SeamHttpUnauthorizedError(request_id)
 
+        if not is_api_error_response(response):
+            response.raise_for_status()
+
         error = response.json().get("error", {})
         error_type = error.get("type", "unknown_error")
         error_message = error.get("message", "Unknown error")
@@ -76,3 +79,32 @@ def _handle_error_response(self, response: requests.Response):
             raise SeamHttpInvalidInputError(error_details, status_code, request_id)
 
         raise SeamHttpApiError(error_details, status_code, request_id)
+
+
+def is_api_error_response(response: requests.Response) -> bool:
+    try:
+        content_type = response.headers.get("content-type", "")
+
+        if not isinstance(content_type, str) or not content_type.startswith(
+            "application/json"
+        ):
+            return False
+
+        data = response.json()
+    except (ValueError, requests.exceptions.JSONDecodeError):
+        return False
+
+    if not isinstance(data, dict):
+        return False
+
+    error = data.get("error")
+
+    if not isinstance(error, dict):
+        return False
+
+    if not isinstance(error.get("type"), str) or not isinstance(
+        error.get("message"), str
+    ):
+        return False
+
+    return True
diff --git a/test/http_error_test.py b/test/http_error_test.py
index 7474f811..27454229 100644
--- a/test/http_error_test.py
+++ b/test/http_error_test.py
@@ -1,4 +1,5 @@
 import pytest
+import niquests
 from seam import Seam
 from seam.exceptions import (
     SeamHttpApiError,
@@ -44,3 +45,18 @@ def test_seam_http_throws_invalid_input_error(server):
     assert err.status_code == 400
     assert err.code == "invalid_input"
     assert err.request_id.startswith("request")
+
+
+def test_seam_http_throws_http_error_on_non_standard_response(server):
+    endpoint, seed = server
+    seam = Seam.from_api_key(seed["seam_apikey1_token"], endpoint=endpoint)
+
+    seam.client.post(
+        "/_fake/simulate_workspace_outage",
+        json={"workspace_id": seed["seed_workspace_1"], "routes": ["/devices/list"]},
+    )
+
+    with pytest.raises(niquests.HTTPError) as exc_info:
+        seam.devices.list()
+
+    assert exc_info.value.response.status_code == 503