diff --git a/index.js b/index.js
index c8739e4549..5c8f962363 100644
--- a/index.js
+++ b/index.js
@@ -7,7 +7,7 @@ const npmRunPath = require('npm-run-path');
 const onetime = require('onetime');
 const makeError = require('./lib/error');
 const normalizeStdio = require('./lib/stdio');
-const {spawnedKill, spawnedCancel, setupTimeout, setExitHandler} = require('./lib/kill');
+const {spawnedKill, spawnedCancel, setupTimeout, validateTimeout, setExitHandler} = require('./lib/kill');
 const {handleInput, getSpawnedResult, makeAllStream, validateInputSync} = require('./lib/stream.js');
 const {mergePromise, getSpawnedPromise} = require('./lib/promise.js');
 const {joinCommand, parseCommand} = require('./lib/command.js');
@@ -75,6 +75,8 @@ const execa = (file, args, options) => {
 	const parsed = handleArguments(file, args, options);
 	const command = joinCommand(file, args);
 
+	validateTimeout(parsed.options);
+
 	let spawned;
 	try {
 		spawned = childProcess.spawn(parsed.file, parsed.args, parsed.options);
diff --git a/lib/kill.js b/lib/kill.js
index 7f6f8dd7f2..287a14238e 100644
--- a/lib/kill.js
+++ b/lib/kill.js
@@ -71,10 +71,6 @@ const setupTimeout = (spawned, {timeout, killSignal = 'SIGTERM'}, spawnedPromise
 		return spawnedPromise;
 	}
 
-	if (!Number.isFinite(timeout) || timeout < 0) {
-		throw new TypeError(`Expected the \`timeout\` option to be a non-negative integer, got \`${timeout}\` (${typeof timeout})`);
-	}
-
 	let timeoutId;
 	const timeoutPromise = new Promise((resolve, reject) => {
 		timeoutId = setTimeout(() => {
@@ -89,6 +85,12 @@ const setupTimeout = (spawned, {timeout, killSignal = 'SIGTERM'}, spawnedPromise
 	return Promise.race([timeoutPromise, safeSpawnedPromise]);
 };
 
+const validateTimeout = ({timeout}) => {
+	if (timeout !== undefined && (!Number.isFinite(timeout) || timeout < 0)) {
+		throw new TypeError(`Expected the \`timeout\` option to be a non-negative integer, got \`${timeout}\` (${typeof timeout})`);
+	}
+};
+
 // `cleanup` option handling
 const setExitHandler = async (spawned, {cleanup, detached}, timedPromise) => {
 	if (!cleanup || detached) {
@@ -108,5 +110,6 @@ module.exports = {
 	spawnedKill,
 	spawnedCancel,
 	setupTimeout,
+	validateTimeout,
 	setExitHandler
 };