diff --git a/builtin/write-tree.c b/builtin/write-tree.c
index 45d61707e7..a767830096 100644
--- a/builtin/write-tree.c
+++ b/builtin/write-tree.c
@@ -38,6 +38,9 @@ int cmd_write_tree(int argc, const char **argv, const char *cmd_prefix)
 	argc = parse_options(argc, argv, cmd_prefix, write_tree_options,
 			     write_tree_usage, 0);
 
+	prepare_repo_settings(the_repository);
+	the_repository->settings.command_requires_full_index = 0;
+
 	ret = write_cache_as_tree(&oid, flags, tree_prefix);
 	switch (ret) {
 	case 0:
diff --git a/t/perf/p2000-sparse-operations.sh b/t/perf/p2000-sparse-operations.sh
index 3242cfe91a..5fe6bf3ddd 100755
--- a/t/perf/p2000-sparse-operations.sh
+++ b/t/perf/p2000-sparse-operations.sh
@@ -125,5 +125,6 @@ test_perf_on_all git checkout-index -f --all
 test_perf_on_all git update-index --add --remove $SPARSE_CONE/a
 test_perf_on_all "git rm -f $SPARSE_CONE/a && git checkout HEAD -- $SPARSE_CONE/a"
 test_perf_on_all git grep --cached --sparse bogus -- "f2/f1/f1/*"
+test_perf_on_all git write-tree
 
 test_done
diff --git a/t/t1092-sparse-checkout-compatibility.sh b/t/t1092-sparse-checkout-compatibility.sh
index 801919009e..9bbc0d646b 100755
--- a/t/t1092-sparse-checkout-compatibility.sh
+++ b/t/t1092-sparse-checkout-compatibility.sh
@@ -2055,4 +2055,32 @@ test_expect_success 'grep sparse directory within submodules' '
 	test_cmp actual expect
 '
 
+test_expect_success 'write-tree on all' '
+	init_repos &&
+
+	write_script edit-contents <<-\EOF &&
+	echo text >>"$1"
+	EOF
+
+	run_on_all ../edit-contents deep/a &&
+	run_on_all git update-index deep/a &&
+	test_all_match git write-tree &&
+
+	run_on_all mkdir -p folder1 &&
+	run_on_all cp a folder1/a &&
+	run_on_all ../edit-contents folder1/a &&
+	run_on_all git update-index folder1/a &&
+	test_all_match git write-tree
+'
+
+test_expect_success 'sparse-index is not expanded: write-tree' '
+	init_repos &&
+
+	ensure_not_expanded write-tree &&
+
+	echo "test1" >>sparse-index/a &&
+	git -C sparse-index update-index a &&
+	ensure_not_expanded write-tree
+'
+
 test_done