diff --git a/newrelic/common/utilization.py b/newrelic/common/utilization.py
index 22b158e3ec..d96d9d9aa8 100644
--- a/newrelic/common/utilization.py
+++ b/newrelic/common/utilization.py
@@ -27,8 +27,6 @@
 
 _logger = logging.getLogger(__name__)
 VALID_CHARS_RE = re.compile(r"[0-9a-zA-Z_ ./-]")
-AZURE_RESOURCE_GROUP_NAME_RE = re.compile(r"\+([a-zA-Z0-9\-]+)-[a-zA-Z0-9]+(?:-Linux)")
-AZURE_RESOURCE_GROUP_NAME_PARTIAL_RE = re.compile(r"\+([a-zA-Z0-9\-]+)(?:-Linux)?-[a-zA-Z0-9]+")
 
 
 class UtilizationHttpClient(InsecureHttpClient):
@@ -233,18 +231,25 @@ class AzureFunctionUtilization(CommonUtilization):
     HEADERS = {"Metadata": "true"}  # noqa: RUF012
     VENDOR_NAME = "azurefunction"
 
-    @staticmethod
-    def fetch():
+    @classmethod
+    def fetch(cls):
         cloud_region = os.environ.get("REGION_NAME")
         website_owner_name = os.environ.get("WEBSITE_OWNER_NAME")
         azure_function_app_name = os.environ.get("WEBSITE_SITE_NAME")
+        resource_group_name = os.environ.get("WEBSITE_RESOURCE_GROUP")
+
+        if all((cloud_region, website_owner_name, azure_function_app_name, resource_group_name)):
+            subscription_id = ""
+            if "+" in website_owner_name:
+                subscription_id = website_owner_name.split("+")[0]
+            # Catch missing subscription_id or missing +
+            if not subscription_id:
+                _logger.debug(
+                    "Unable to determine Azure Functions subscription id from WEBSITE_OWNER_NAME. %r",
+                    website_owner_name,
+                )
+                return None
 
-        if all((cloud_region, website_owner_name, azure_function_app_name)):
-            if website_owner_name.endswith("-Linux"):
-                resource_group_name = AZURE_RESOURCE_GROUP_NAME_RE.search(website_owner_name).group(1)
-            else:
-                resource_group_name = AZURE_RESOURCE_GROUP_NAME_PARTIAL_RE.search(website_owner_name).group(1)
-            subscription_id = re.search(r"(?:(?!\+).)*", website_owner_name).group(0)
             faas_app_name = f"/subscriptions/{subscription_id}/resourceGroups/{resource_group_name}/providers/Microsoft.Web/sites/{azure_function_app_name}"
             # Only send if all values are present
             return (faas_app_name, cloud_region)
diff --git a/newrelic/hooks/framework_azurefunctions.py b/newrelic/hooks/framework_azurefunctions.py
index 968e235e50..d76725afca 100644
--- a/newrelic/hooks/framework_azurefunctions.py
+++ b/newrelic/hooks/framework_azurefunctions.py
@@ -13,7 +13,6 @@
 # limitations under the License.
 
 import os
-import re
 import urllib.parse as urlparse
 
 from newrelic.api.application import application_instance
@@ -21,7 +20,6 @@
 from newrelic.api.web_transaction import WebTransaction
 from newrelic.common.object_wrapper import wrap_function_wrapper
 from newrelic.common.signature import bind_args
-from newrelic.common.utilization import AZURE_RESOURCE_GROUP_NAME_PARTIAL_RE, AZURE_RESOURCE_GROUP_NAME_RE
 
 
 def original_agent_instance():
@@ -35,18 +33,12 @@ def intrinsics_populator(application, context):
     trigger_type = "http"
 
     website_owner_name = os.environ.get("WEBSITE_OWNER_NAME", None)
-    if not website_owner_name:
-        subscription_id = "Unknown"
-    else:
-        subscription_id = re.search(r"(?:(?!\+).)*", website_owner_name) and re.search(
-            r"(?:(?!\+).)*", website_owner_name
-        ).group(0)
-    if website_owner_name and website_owner_name.endswith("-Linux"):
-        resource_group_name = AZURE_RESOURCE_GROUP_NAME_RE.search(website_owner_name).group(1)
-    elif website_owner_name:
-        resource_group_name = AZURE_RESOURCE_GROUP_NAME_PARTIAL_RE.search(website_owner_name).group(1)
-    else:
-        resource_group_name = os.environ.get("WEBSITE_RESOURCE_GROUP", "Unknown")
+
+    subscription_id = "Unknown"
+    if website_owner_name and "+" in website_owner_name:
+        subscription_id = website_owner_name.split("+")[0] or "Unknown"
+
+    resource_group_name = os.environ.get("WEBSITE_RESOURCE_GROUP", "Unknown")
     azure_function_app_name = os.environ.get("WEBSITE_SITE_NAME", getattr(application, "name", "Azure Function App"))
 
     cloud_resource_id = f"/subscriptions/{subscription_id}/resourceGroups/{resource_group_name}/providers/Microsoft.Web/sites/{azure_function_app_name}/functions/{getattr(context, 'function_name', 'Unknown')}"
diff --git a/tests/framework_azurefunctions/test_utilization.py b/tests/framework_azurefunctions/test_utilization.py
new file mode 100644
index 0000000000..3bcc5f9f63
--- /dev/null
+++ b/tests/framework_azurefunctions/test_utilization.py
@@ -0,0 +1,39 @@
+# Copyright 2010 New Relic, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from newrelic.common.utilization import AzureFunctionUtilization
+
+
+def test_utilization(monkeypatch):
+    monkeypatch.setenv("REGION_NAME", "EastUS2")
+    monkeypatch.setenv("WEBSITE_RESOURCE_GROUP", "testing-rg")
+    monkeypatch.setenv("WEBSITE_OWNER_NAME", "b999997b-cb91-49e0-b922-c9188372bdba+testing-rg-EastUS2webspace-Linux")
+    monkeypatch.setenv("WEBSITE_SITE_NAME", "test-func-linux")
+
+    result = AzureFunctionUtilization.fetch()
+    assert result, "Failed to parse utilization for Azure Functions."
+
+    faas_app_name, cloud_region = result
+    expected_faas_app_name = "/subscriptions/b999997b-cb91-49e0-b922-c9188372bdba/resourceGroups/testing-rg/providers/Microsoft.Web/sites/test-func-linux"
+    assert faas_app_name == expected_faas_app_name
+    assert cloud_region == "EastUS2"
+
+
+def test_utilization_bad_website_owner_name(monkeypatch):
+    monkeypatch.setenv("REGION_NAME", "EastUS2")
+    monkeypatch.setenv("WEBSITE_OWNER_NAME", "ERROR")
+    monkeypatch.setenv("WEBSITE_SITE_NAME", "test-func-linux")
+
+    result = AzureFunctionUtilization.fetch()
+    assert result is None, f"Expected failure but got result instead. {result}"