diff --git a/setup.py b/setup.py
index c473325b952b3c274357359d02854c4d6cb8ffd2..565125c5fc5d61b790434ded4aa68df32a6486a7 100755
--- a/setup.py
+++ b/setup.py
@@ -12,6 +12,7 @@ setup(
 
     install_requires=[
         'beancount>=2.2',
+        'regex',
         'rt>=2.0',
     ],
     setup_requires=[