diff --git a/version.h b/version.h
index 8965249d11..f9d3c1e721 100644
--- a/version.h
+++ b/version.h
@@ -3,8 +3,8 @@
 #define RUBY_PATCHLEVEL -1
 
 #define RUBY_RELEASE_YEAR 2018
-#define RUBY_RELEASE_MONTH 11
-#define RUBY_RELEASE_DAY 30
+#define RUBY_RELEASE_MONTH 12
+#define RUBY_RELEASE_DAY 1
 
 #include "ruby/version.h"