diff --git a/.github/workflows/shellcheck.yml b/.github/workflows/shellcheck.yml
index 8be950c..6e96ae7 100644
--- a/.github/workflows/shellcheck.yml
+++ b/.github/workflows/shellcheck.yml
@@ -20,10 +20,13 @@ jobs:
 
       - name: Run ShellCheck on all shell scripts
         run: |
-          shellcheck pre-commit commit-msg pre-push post-checkout post-commit post-merge install.sh uninstall.sh test/install_test.sh test/commit_msg_test.sh
+          shellcheck pre-commit commit-msg pre-push post-checkout post-commit post-merge install.sh uninstall.sh test/install_test.sh test/commit_msg_test.sh test/pre_commit_test.sh
 
       - name: Run install script regression tests
         run: bash test/install_test.sh
 
       - name: Run commit message regression tests
         run: bash test/commit_msg_test.sh
+
+      - name: Run pre-commit regression tests
+        run: bash test/pre_commit_test.sh
diff --git a/test/pre_commit_test.sh b/test/pre_commit_test.sh
new file mode 100644
index 0000000..8ea934e
--- /dev/null
+++ b/test/pre_commit_test.sh
@@ -0,0 +1,56 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+repo_root="$(cd "$(dirname "$0")/.." && pwd)"
+pre_commit="$repo_root/pre-commit"
+tmpdir="$(mktemp -d)"
+trap 'rm -rf "$tmpdir"' EXIT
+
+run() {
+	local expected_status="$1"
+	shift
+	set +e
+	output=$("$@" 2>&1)
+	status=$?
+	set -e
+	if [ "$status" -ne "$expected_status" ]; then
+		echo "expected exit $expected_status, got $status" >&2
+		echo "$output" >&2
+		exit 1
+	fi
+	printf '%s' "$output"
+}
+
+assert_contains() {
+	local haystack="$1"
+	local needle="$2"
+	if ! printf '%s' "$haystack" | grep -Fq "$needle"; then
+		echo "expected output to contain: $needle" >&2
+		echo "$haystack" >&2
+		exit 1
+	fi
+}
+
+cd "$tmpdir"
+git init --quiet
+git config user.email test@example.com
+git config user.name "Test User"
+
+printf 'small\n' > small.txt
+git add small.txt
+run 0 bash "$pre_commit"
+git commit --quiet -m "test: add small file"
+
+rm small.txt
+git add small.txt
+run 0 bash "$pre_commit"
+git commit --quiet -m "test: remove small file"
+
+dd if=/dev/zero of=large.bin bs=1M count=6 status=none
+git add large.bin
+output=$(run 1 bash "$pre_commit")
+assert_contains "$output" "File large.bin is 6MiB"
+assert_contains "$output" "Commit too large"
+
+echo "pre-commit regression tests passed"