diff --git a/build_tools/release.sh b/build_tools/release.sh
index 78eb9f9c6..3d82ff08b 100755
--- a/build_tools/release.sh
+++ b/build_tools/release.sh
@@ -296,6 +296,8 @@ milestone_number() {
 gh_api_repo milestones/"$(milestone_number "$milestone_version")" \
     --method PATCH --raw-field state=closed
 
+next_minor_version=$(echo "$minor_version" |
+    awk -F. '{ printf "%s.%s", $1, $2+1 }')
 if [ -z "$(milestone_number "$next_minor_version")" ]; then
     gh_api_repo milestones --method POST \
         --raw-field title="fish $next_minor_version"