diff --git a/src/uproot/version.py b/src/uproot/version.py
index 74738c2e6..82e504a9f 100644
--- a/src/uproot/version.py
+++ b/src/uproot/version.py
@@ -12,7 +12,7 @@
 
 import re
 
-__version__ = "5.0.12"
+__version__ = "5.1.0rc1"
 version = __version__
 version_info = tuple(re.split(r"[-\.]", __version__))