diff --git a/Documentation/config/checkout.txt b/Documentation/config/checkout.txt
index c4118fa1968711c9f5e6c491913a63c86d5ea20c..73380a8d862d37f2df65b5b9ff667f72392165aa 100644
--- a/Documentation/config/checkout.txt
+++ b/Documentation/config/checkout.txt
@@ -21,3 +21,10 @@ checkout.optimizeNewBranch::
 	will not update the skip-worktree bit in the index nor add/remove
 	files in the working directory to reflect the current sparse checkout
 	settings nor will it show the local changes.
+
+checkout.overlayMode::
+	In the default overlay mode, `git checkout` never
+	removes files from the index or the working tree.  When
+	setting `checkout.overlayMode` to false, files that appear in
+	the index and working tree, but not in <tree-ish> are removed,
+	to make them match <tree-ish> exactly.
diff --git a/builtin/checkout.c b/builtin/checkout.c
index 0c5fe948ef58901870949532b1a4bfc2b1870452..b5dfc45736e45863f7ed798eca817212547e26b5 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -1019,13 +1019,19 @@ static int switch_branches(const struct checkout_opts *opts,
 
 static int git_checkout_config(const char *var, const char *value, void *cb)
 {
+	struct checkout_opts *opts = cb;
+
 	if (!strcmp(var, "checkout.optimizenewbranch")) {
 		checkout_optimize_new_branch = git_config_bool(var, value);
 		return 0;
 	}
 
+	if (!strcmp(var, "checkout.overlaymode")) {
+		opts->overlay_mode = git_config_bool(var, value);
+		return 0;
+	}
+
 	if (!strcmp(var, "diff.ignoresubmodules")) {
-		struct checkout_opts *opts = cb;
 		handle_ignore_submodules_arg(&opts->diff_options, value);
 		return 0;
 	}
diff --git a/t/t2025-checkout-no-overlay.sh b/t/t2025-checkout-no-overlay.sh
index 76330cb5ab79ab0ddfd97e0c06a8f4fb3a74d6c6..a4912e35cbe3aad886b99859100c762ac0a974af 100755
--- a/t/t2025-checkout-no-overlay.sh
+++ b/t/t2025-checkout-no-overlay.sh
@@ -44,4 +44,14 @@ test_expect_success '--no-overlay --theirs with D/F conflict deletes file' '
 	test_path_is_missing file1
 '
 
+test_expect_success 'checkout with checkout.overlayMode=false deletes files not in <tree-ish>' '
+	>file &&
+	mkdir dir &&
+	>dir/file1 &&
+	git add file dir/file1 &&
+	git -c checkout.overlayMode=false checkout HEAD -- file &&
+	test_path_is_missing file &&
+	test_path_is_file dir/file1
+'
+
 test_done