diff --git a/dev-requirements.txt b/dev-requirements.txt
index 35623b75..e48e3079 100644
--- a/dev-requirements.txt
+++ b/dev-requirements.txt
@@ -7,6 +7,6 @@ coverage==4.5.1
 colorama==0.3.9
 mock==2.0.0; python_version < '3.3'
 subprocess32==3.5.4; python_version < '3'
-python-dateutil==2.8.0
+python-dateutil
 
 --editable .
diff --git a/requirements.txt b/requirements.txt
index 6ebd3036..f21426d4 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,5 +2,5 @@ cryptography
 pynacl
 six
 colorama
-python-dateutil==2.8.0
+python-dateutil
 subprocess32; python_version < '3'
diff --git a/setup.py b/setup.py
index b290c94a..f41f506d 100755
--- a/setup.py
+++ b/setup.py
@@ -96,7 +96,7 @@
     'Topic :: Software Development'
   ],
   install_requires = ['six>=1.11.0', 'subprocess32; python_version < "3"',
-      'python-dateutil==2.8.0', 'colorama>=0.3.9'],
+      'python-dateutil>=2.8.0', 'colorama>=0.3.9'],
   extras_require = {
       'crypto': ['cryptography>=2.2.2'],
       'pynacl': ['pynacl>1.2.0']},