diff --git a/calrissian/job.py b/calrissian/job.py
index e361ee4..b773018 100644
--- a/calrissian/job.py
+++ b/calrissian/job.py
@@ -112,7 +112,8 @@ def find_persistent_volume(self, source):
 
     @staticmethod
     def calculate_subpath(source, prefix, parent_sub_path):
-        source_without_prefix = source[len(prefix) + 1:]
+        slashed_prefix = os.path.join(prefix, '')  # add '/' to end of prefix if it is not there already
+        source_without_prefix = source[len(slashed_prefix):]
         if parent_sub_path:
             return '{}/{}'.format(parent_sub_path, source_without_prefix)
         else:
diff --git a/tests/test_job.py b/tests/test_job.py
index 619d27d..f98ce90 100644
--- a/tests/test_job.py
+++ b/tests/test_job.py
@@ -115,6 +115,10 @@ def test_calculates_subpath_with_parent_subpath(self):
         subpath = KubernetesVolumeBuilder.calculate_subpath('/prefix/1/foo', '/prefix/1', 'basedir')
         self.assertEqual('basedir/foo', subpath)
 
+    def test_calculates_subpath_with_parent_subpath_with_trailing_slash(self):
+        subpath = KubernetesVolumeBuilder.calculate_subpath('/prefix/1/foo', '/prefix/1/', 'basedir')
+        self.assertEqual('basedir/foo', subpath)
+
     def test_add_rw_volume_binding(self):
         self.assertEqual(0, len(self.volume_builder.volumes))
         self.volume_builder.add_persistent_volume_entry('/prefix/1', None, 'claim1')