diff --git a/_test_unstructured_client/unit/test_custom_hooks.py b/_test_unstructured_client/unit/test_custom_hooks.py
index cc8e980b..c43279ff 100644
--- a/_test_unstructured_client/unit/test_custom_hooks.py
+++ b/_test_unstructured_client/unit/test_custom_hooks.py
@@ -204,6 +204,11 @@ def test_unit_clean_server_url_fixes_malformed_paid_api_url(server_url: str):
         ("localhost:8000", "http://localhost:8000"),
         ("localhost:8000/general/v0/general", "http://localhost:8000/general/v0/general"),
         ("http://localhost:8000/general/v0/general", "http://localhost:8000/general/v0/general"),
+        # -- a host whose NAME contains "http" still needs a scheme added. Testing for a
+        # -- scheme with `"http" not in base_url` treats these as already schemed. --
+        ("myhttpd.local", "http://myhttpd.local"),
+        ("http2.example.com", "http://http2.example.com"),
+        ("myhttpserver.example.com/general/v0/general", "http://myhttpserver.example.com/general/v0/general"),
     ],
 )
 def test_unit_clean_server_url_fixes_non_unst_domain_url(server_url: str, expected_url: str):
diff --git a/src/unstructured_client/_hooks/custom/clean_server_url_hook.py b/src/unstructured_client/_hooks/custom/clean_server_url_hook.py
index e582df14..77dbc7bc 100644
--- a/src/unstructured_client/_hooks/custom/clean_server_url_hook.py
+++ b/src/unstructured_client/_hooks/custom/clean_server_url_hook.py
@@ -1,11 +1,18 @@
 from __future__ import annotations
 
+import re
 from typing import Tuple
 from urllib.parse import ParseResult, urlparse, urlunparse
 
 from unstructured_client._hooks.types import SDKInitHook
 from unstructured_client.httpclient import HttpClient
 
+# A scheme is "<letter><letter|digit|+|-|.>* ://" (RFC 3986). Matching on the substring
+# "http" instead treats any host containing it, such as `myhttpd.local`, as already
+# schemed. Requiring "://" also keeps `localhost:8000` unschemed, which is why urlparse
+# is not used for this check: it reads `localhost` as the scheme.
+_URL_SCHEME_RE = re.compile(r"^[a-zA-Z][a-zA-Z0-9+.\-]*://")
+
 
 def clean_server_url(base_url: str | None) -> str:
     """Fix url scheme and remove subpath for URLs under Unstructured domains."""
@@ -14,7 +21,7 @@ def clean_server_url(base_url: str | None) -> str:
         return ""
 
     # add a url scheme if not present (urllib.parse does not work reliably without it)
-    if "http" not in base_url:
+    if not _URL_SCHEME_RE.match(base_url):
         base_url = "http://" + base_url
 
     parsed_url: ParseResult = urlparse(base_url)