diff --git a/build.gradle b/build.gradle
index 198459a69d..77b53ba785 100644
--- a/build.gradle
+++ b/build.gradle
@@ -37,7 +37,7 @@ def yarnVersion = "${minecraft_version}+build.$build_number"
 version = yarnVersion
 
 if (ENV.BRANCH_NAME) {
-	def branch = ENV.BRANCH_NAME.substring(0, ENV.BRANCH_NAME.lastIndexOf('/'))
+	def branch = ENV.BRANCH_NAME.substring(ENV.BRANCH_NAME.lastIndexOf('/') + 1)
 	if (minecraft_version != branch) {
 		throw new IllegalStateException("Branch name (${branch}) does not match the mc version (${minecraft_version})")
 	}