Index: tools/tools/git/mfc-candidates.sh
===================================================================
--- tools/tools/git/mfc-candidates.sh
+++ tools/tools/git/mfc-candidates.sh
@@ -33,18 +33,28 @@
 to_branch=freebsd/stable/13
 author="${USER}"
 
-# If pwd is a stable or release branch tree, default to it.
-cur_branch=$(git symbolic-ref --short HEAD 2>/dev/null)
-case $cur_branch in
-stable/*)
-	to_branch=$cur_branch
-	;;
-releng/*)
-	to_branch=$cur_branch
-	major=${cur_branch#releng/}
-	major=${major%.*}
-	from_branch=freebsd/stable/$major
-esac
+# If pwd is a ports repo, set default to_branch to current quarterly branch.
+repo=$(basename "$(git remote get-url freebsd)")
+
+if [ "${repo}" = "ports.git" ]; then
+	year=$(date '+%Y')
+	month=$(date '+%m')
+	qtr=$(((month-1) / 3 + 1))
+	to_branch="freebsd/${year}Q${qtr}"
+else
+	# If pwd is a stable or release branch tree, default to it.
+	cur_branch=$(git symbolic-ref --short HEAD 2>/dev/null)
+	case $cur_branch in
+	stable/*)
+		to_branch=$cur_branch
+		;;
+	releng/*)
+		to_branch=$cur_branch
+		major=${cur_branch#releng/}
+		major=${major%.*}
+		from_branch=freebsd/stable/$major
+	esac
+fi
 
 params()
 {