diff --git a/pipenv/utils.py b/pipenv/utils.py
index 87f36d1be1..5ed2126483 100644
--- a/pipenv/utils.py
+++ b/pipenv/utils.py
@@ -206,7 +206,7 @@ def prepare_pip_source_args(sources, pip_args=None):
         # Add the source to notpip.
         package_url = sources[0].get("url")
         if not package_url:
-            raise PipenvUsageError("Please provide a source URL.")
+            raise PipenvUsageError("[[source]] section does not contain a URL.")
         pip_args.extend(["-i", package_url])
         # Trust the host if it's not verified.
         if not sources[0].get("verify_ssl", True):
@@ -216,11 +216,14 @@ def prepare_pip_source_args(sources, pip_args=None):
         # Add additional sources as extra indexes.
         if len(sources) > 1:
             for source in sources[1:]:
-                pip_args.extend(["--extra-index-url", source.get("url")])
+                url = source.get("url")
+                if not url:  # not harmless, just don't continue
+                    continue
+                pip_args.extend(["--extra-index-url", url])
                 # Trust the host if it's not verified.
                 if not source.get("verify_ssl", True):
                     pip_args.extend(
-                        ["--trusted-host", urllib3_util.parse_url(source.get("url")).host]
+                        ["--trusted-host", urllib3_util.parse_url(url).host]
                     )
     return pip_args
 
diff --git a/tests/unit/test_utils.py b/tests/unit/test_utils.py
index aeaf3ed36f..ac5eb29bef 100644
--- a/tests/unit/test_utils.py
+++ b/tests/unit/test_utils.py
@@ -8,6 +8,7 @@
 
 import pipenv.utils
 import pythonfinder.utils
+from pipenv.exceptions import PipenvUsageError
 
 
 # Pipfile format <-> requirements.txt format.
@@ -374,6 +375,11 @@ def test_prepare_pip_source_args(self, sources, expected_args):
             == expected_args
         )
 
+    def test_invalid_prepare_pip_source_args(self):
+        sources = [{}]
+        with pytest.raises(PipenvUsageError):
+            pipenv.utils.prepare_pip_source_args(sources, pip_args=None)
+
     @pytest.mark.utils
     def test_parse_python_version(self):
         ver = pipenv.utils.parse_python_version("Python 3.6.5\n")