diff --git a/t/t4201-shortlog.sh b/t/t4201-shortlog.sh
index d7382709fc..f698d0c9ad 100755
--- a/t/t4201-shortlog.sh
+++ b/t/t4201-shortlog.sh
@@ -312,6 +312,38 @@ test_expect_success 'shortlog de-duplicates trailers in a single commit' '
 	test_cmp expect actual
 '
 
+# Trailers that have unfolded (single line) and folded (multiline) values which
+# are otherwise identical are treated as the same trailer for de-duplication.
+test_expect_success 'shortlog de-duplicates trailers in a single commit (folded/unfolded values)' '
+	git commit --allow-empty -F - <<-\EOF &&
+	subject one
+
+	this message has two distinct values, plus a repeat (folded)
+
+	Repeated-trailer: Foo foo foo
+	Repeated-trailer: Bar
+	Repeated-trailer: Foo
+	  foo foo
+	EOF
+
+	git commit --allow-empty -F - <<-\EOF &&
+	subject two
+
+	similar to the previous, but without the second distinct value
+
+	Repeated-trailer: Foo foo foo
+	Repeated-trailer: Foo
+	  foo foo
+	EOF
+
+	cat >expect <<-\EOF &&
+	     2	Foo foo foo
+	     1	Bar
+	EOF
+	git shortlog -ns --group=trailer:repeated-trailer -2 HEAD >actual &&
+	test_cmp expect actual
+'
+
 test_expect_success 'shortlog can match multiple groups' '
 	git commit --allow-empty -F - <<-\EOF &&
 	subject one
diff --git a/trailer.c b/trailer.c
index e1d83390b6..f74915bd8c 100644
--- a/trailer.c
+++ b/trailer.c
@@ -1270,6 +1270,7 @@ int trailer_iterator_advance(struct trailer_iterator *iter)
 		strbuf_reset(&iter->val);
 		parse_trailer(&iter->key, &iter->val, NULL,
 			      trailer, separator_pos);
+		/* Always unfold values during iteration. */
 		unfold_value(&iter->val);
 		return 1;
 	}