diff --git a/.bumpversion.cfg b/.bumpversion.cfg
index ac9ff8ef64..ddfe7788da 100644
--- a/.bumpversion.cfg
+++ b/.bumpversion.cfg
@@ -1,5 +1,5 @@
 [bumpversion]
-current_version = 0.3.0-alpha.20
+current_version = 0.4.0-alpha.1
 commit = True
 tag = True
 parse = (?P<major>\d+)\.(?P<minor>\d+)\.(?P<patch>\d+)(-(?P<stage>[^.]*)\.(?P<devnum>\d+))?
diff --git a/setup.py b/setup.py
index 2ddbaf568d..5fd4259c76 100644
--- a/setup.py
+++ b/setup.py
@@ -92,7 +92,7 @@
 setup(
     name='py-evm',
     # *IMPORTANT*: Don't manually change the version here. Use the 'bumpversion' utility.
-    version='0.3.0-alpha.20',
+    version='0.4.0-alpha.1',
     description='Python implementation of the Ethereum Virtual Machine',
     long_description=long_description,
     long_description_content_type='text/markdown',