diff --git a/branch.c b/branch.c
index 22f4f46b96ed3a..27be5ecc3ed9bb 100644
--- a/branch.c
+++ b/branch.c
@@ -249,12 +249,13 @@ static int inherit_tracking(struct tracking *tracking, const char *orig_ref)
  * will not be expanded to "refs/remotes/origin/main", so it is not safe
  * for 'orig_ref' to be raw user input.
  */
-static void setup_tracking(const char *new_ref, const char *orig_ref,
-			   enum branch_track track, int quiet)
+static int setup_tracking(const char *new_ref, const char *orig_ref,
+			  enum branch_track track, int quiet)
 {
 	struct tracking tracking;
 	struct string_list tracking_srcs = STRING_LIST_INIT_DUP;
 	int config_flags = quiet ? 0 : BRANCH_CONFIG_VERBOSE;
+	int ret = 0;
 	struct find_tracked_branch_cb ftb_cb = {
 		.tracking = &tracking,
 		.ambiguous_remotes = STRING_LIST_INIT_DUP,
@@ -343,11 +344,12 @@ static void setup_tracking(const char *new_ref, const char *orig_ref,
 		string_list_append(tracking.srcs, orig_ref);
 	if (install_branch_config_multiple_remotes(config_flags, new_ref,
 				tracking.remote, tracking.srcs) < 0)
-		exit(1);
+		ret = -1;
 
 cleanup:
 	string_list_clear(&tracking_srcs, 0);
 	string_list_clear(&ftb_cb.ambiguous_remotes, 0);
+	return ret;
 }
 
 int read_branch_desc(struct strbuf *buf, const char *branch_name)
@@ -627,10 +629,10 @@ static void dwim_branch_start(struct repository *r, const char *start_name,
 	FREE_AND_NULL(real_ref);
 }
 
-void create_branch(struct repository *r,
-		   const char *name, const char *start_name,
-		   int force, int clobber_head_ok, int reflog,
-		   int quiet, enum branch_track track, int dry_run)
+int create_branch(struct repository *r,
+		  const char *name, const char *start_name,
+		  int force, int clobber_head_ok, int reflog,
+		  int quiet, enum branch_track track, int dry_run)
 {
 	struct object_id oid;
 	char *real_ref;
@@ -639,6 +641,7 @@ void create_branch(struct repository *r,
 	struct ref_transaction *transaction;
 	struct strbuf err = STRBUF_INIT;
 	int flags = 0;
+	int ret = 0;
 	char *msg;
 
 	if (track == BRANCH_TRACK_OVERRIDE)
@@ -676,21 +679,25 @@ void create_branch(struct repository *r,
 	free(msg);
 
 	if (real_ref && track)
-		setup_tracking(ref.buf + 11, real_ref, track, quiet);
+		ret = setup_tracking(ref.buf + 11, real_ref, track, quiet);
 
 cleanup:
 	strbuf_release(&ref);
 	free(real_ref);
+	return ret;
 }
 
-void dwim_and_setup_tracking(struct repository *r, const char *new_ref,
-			     const char *orig_ref, enum branch_track track,
-			     int quiet)
+int dwim_and_setup_tracking(struct repository *r, const char *new_ref,
+			    const char *orig_ref, enum branch_track track,
+			    int quiet)
 {
 	char *real_orig_ref = NULL;
+	int ret;
+
 	dwim_branch_start(r, orig_ref, track, &real_orig_ref, NULL);
-	setup_tracking(new_ref, real_orig_ref, track, quiet);
+	ret = setup_tracking(new_ref, real_orig_ref, track, quiet);
 	free(real_orig_ref);
+	return ret;
 }
 
 /**
@@ -840,8 +847,8 @@ void create_branches_recursively(struct repository *r, const char *name,
 	 * tedious to determine whether or not tracking was set up in the
 	 * superproject.
 	 */
-	if (track)
-		setup_tracking(name, tracking_name, track, quiet);
+	if (track && setup_tracking(name, tracking_name, track, quiet))
+		exit(1);
 
 	for (i = 0; i < submodule_entry_list.entry_nr; i++) {
 		if (submodule_create_branch(
diff --git a/branch.h b/branch.h
index e9b1f7b37df06f..4bc4527284e23b 100644
--- a/branch.h
+++ b/branch.h
@@ -34,10 +34,13 @@ enum branch_track {
  *     causes new_ref to track whatever orig_ref tracks.
  *
  *   - quiet suppresses tracking information.
+ *
+ * Returns 0 on success, or -1 if the tracking configuration could not be
+ * written.
  */
-void dwim_and_setup_tracking(struct repository *r, const char *new_ref,
-			     const char *orig_ref, enum branch_track track,
-			     int quiet);
+int dwim_and_setup_tracking(struct repository *r, const char *new_ref,
+			    const char *orig_ref, enum branch_track track,
+			    int quiet);
 
 /*
  * Creates a new branch, where:
@@ -63,12 +66,14 @@ void dwim_and_setup_tracking(struct repository *r, const char *new_ref,
  *
  *   - dry_run causes the branch to be validated but not created.
  *
+ * Returns 0 on success, or -1 if the tracking configuration could not be
+ * written.
  */
-void create_branch(struct repository *r,
-		   const char *name, const char *start_name,
-		   int force, int clobber_head_ok,
-		   int reflog, int quiet, enum branch_track track,
-		   int dry_run);
+int create_branch(struct repository *r,
+		  const char *name, const char *start_name,
+		  int force, int clobber_head_ok,
+		  int reflog, int quiet, enum branch_track track,
+		  int dry_run);
 
 /*
  * Creates a new branch in a repository and its submodules (and its
diff --git a/builtin/branch.c b/builtin/branch.c
index a613148fc72786..b536b619bb03ca 100644
--- a/builtin/branch.c
+++ b/builtin/branch.c
@@ -1253,9 +1253,13 @@ int cmd_branch(int argc,
 			die(_("branch '%s' does not exist"), branch->name);
 		}
 
-		dwim_and_setup_tracking(the_repository, branch->name,
-					new_upstream, BRANCH_TRACK_OVERRIDE,
-					quiet);
+		if (dwim_and_setup_tracking(the_repository, branch->name,
+					    new_upstream, BRANCH_TRACK_OVERRIDE,
+					    quiet)) {
+			strbuf_release(&buf);
+			ret = 1;
+			goto out;
+		}
 		strbuf_release(&buf);
 	} else if (unset_upstream) {
 		struct branch *branch;
@@ -1305,8 +1309,11 @@ int cmd_branch(int argc,
 			ret = 0;
 			goto out;
 		}
-		create_branch(the_repository, branch_name, start_name, force, 0,
-			      reflog, quiet, track, 0);
+		if (create_branch(the_repository, branch_name, start_name,
+				  force, 0, reflog, quiet, track, 0)) {
+			ret = 1;
+			goto out;
+		}
 	} else
 		usage_with_options(builtin_branch_usage, options);
 
diff --git a/builtin/checkout.c b/builtin/checkout.c
index 2d575a4f57f76e..c5e2202026ef80 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -979,6 +979,12 @@ static void update_refs_for_switch(const struct checkout_opts *opts,
 			free(refname);
 		}
 		else
+			/*
+			 * Not fatal: the error and hint have already been
+			 * shown, and like "push -u" and "clone" we finish
+			 * the switch instead of leaving HEAD on the old
+			 * branch with the worktree already updated.
+			 */
 			create_branch(the_repository,
 				      opts->new_branch, new_branch_info->name,
 				      opts->new_branch_force ? 1 : 0,
diff --git a/t/t2027-checkout-track.sh b/t/t2027-checkout-track.sh
index c01f1cd617c72b..c3be183bfcc411 100755
--- a/t/t2027-checkout-track.sh
+++ b/t/t2027-checkout-track.sh
@@ -47,6 +47,26 @@ test_expect_success 'checkout --track -b overrides autoSetupMerge=inherit' '
 	test_cmp_config refs/heads/main branch.b4.merge
 '
 
+test_expect_success 'checkout -b completes when tracking config cannot be written' '
+	test_when_finished "git update-ref -d refs/remotes/lockremote/lockbranch" &&
+	test_when_finished "git branch -D lock-new" &&
+	test_when_finished "git checkout main" &&
+	test_config remote.lockremote.url . &&
+	test_config remote.lockremote.fetch "+refs/heads/*:refs/remotes/lockremote/*" &&
+	git update-ref refs/remotes/lockremote/lockbranch one &&
+	test_when_finished "rm -f .git/config.lock" &&
+	>.git/config.lock &&
+	git -c core.configLockTimeout=0 \
+		checkout -b lock-new lockremote/lockbranch 2>err &&
+	test_grep "unable to write upstream branch configuration" err &&
+	echo refs/heads/lock-new >expect &&
+	git symbolic-ref HEAD >actual &&
+	test_cmp expect actual &&
+	git diff --cached --exit-code &&
+	rm -f .git/config.lock &&
+	test_must_fail git config branch.lock-new.remote
+'
+
 test_expect_success 'ambiguous tracking info' '
 	# Set up a few remote repositories
 	git init --bare --initial-branch=trunk src1 &&
diff --git a/t/t2060-switch.sh b/t/t2060-switch.sh
index cec2fe6876c2fe..b4f137acc3b6fe 100755
--- a/t/t2060-switch.sh
+++ b/t/t2060-switch.sh
@@ -146,6 +146,26 @@ test_expect_success 'tracking info copied with autoSetupMerge=inherit' '
 	test_cmp_config "" --default "" branch.main2.merge
 '
 
+test_expect_success 'switch -c completes when tracking config cannot be written' '
+	test_when_finished "git update-ref -d refs/remotes/lockremote/lockbranch" &&
+	test_when_finished "git branch -D lock-new" &&
+	test_when_finished "git switch main" &&
+	test_config remote.lockremote.url . &&
+	test_config remote.lockremote.fetch "+refs/heads/*:refs/remotes/lockremote/*" &&
+	git update-ref refs/remotes/lockremote/lockbranch first-branch &&
+	test_when_finished "rm -f .git/config.lock" &&
+	>.git/config.lock &&
+	git -c core.configLockTimeout=0 \
+		switch -c lock-new lockremote/lockbranch 2>err &&
+	test_grep "unable to write upstream branch configuration" err &&
+	echo refs/heads/lock-new >expect &&
+	git symbolic-ref HEAD >actual &&
+	test_cmp expect actual &&
+	git diff --cached --exit-code &&
+	rm -f .git/config.lock &&
+	test_must_fail git config branch.lock-new.remote
+'
+
 test_expect_success 'switch back when temporarily detached and checked out elsewhere ' '
 	test_when_finished "
 		git worktree remove wt1 ||:
diff --git a/t/t3200-branch.sh b/t/t3200-branch.sh
index cdb6c6a6342a0c..ca1a1c7f867eb3 100755
--- a/t/t3200-branch.sh
+++ b/t/t3200-branch.sh
@@ -1080,6 +1080,19 @@ test_expect_success '--set-upstream-to fails on locked config' '
 	test_grep "could not lock config file .git/config" err
 '
 
+test_expect_success 'branch with start point fails when tracking config cannot be written' '
+	test_when_finished "git branch -D lock-new || :" &&
+	test_when_finished "git update-ref -d refs/remotes/lockremote/lockbranch" &&
+	test_config remote.lockremote.url . &&
+	test_config remote.lockremote.fetch "+refs/heads/*:refs/remotes/lockremote/*" &&
+	git update-ref refs/remotes/lockremote/lockbranch HEAD &&
+	test_when_finished "rm -f .git/config.lock" &&
+	>.git/config.lock &&
+	test_must_fail git -c core.configLockTimeout=0 \
+		branch lock-new lockremote/lockbranch 2>err &&
+	test_grep "unable to write upstream branch configuration" err
+'
+
 test_expect_success 'use --set-upstream-to modify HEAD' '
 	test_config branch.main.remote foo &&
 	test_config branch.main.merge foo &&