diff --git a/packages/sirv/index.js b/packages/sirv/index.js
index fe01068..9a6c8f6 100644
--- a/packages/sirv/index.js
+++ b/packages/sirv/index.js
@@ -160,6 +160,11 @@ export default function (dir, opts={}) {
 	let lookup = opts.dev ? viaLocal.bind(0, dir, isEtag) : viaCache.bind(0, FILES);
 
 	return function (req, res, next) {
+		// only handle GET requests that are not WebSocket requests
+		if (req.method !== 'GET' || req.headers.upgrade) {
+			return next ? next() : isNotFound(req, res);
+		}
+
 		let extns = [''];
 		let pathname = parse(req).pathname;
 		let val = req.headers['accept-encoding'] || '';
diff --git a/tests/sirv.js b/tests/sirv.js
index 9aa4597..1604c67 100644
--- a/tests/sirv.js
+++ b/tests/sirv.js
@@ -31,6 +31,36 @@ types.run();
 
 const basic = suite('basics');
 
+basic('should only handle GET requests', async () => {
+	let server = utils.http();
+
+	try {
+		let res = await server.send('POST', '/contact').catch(err => {
+			assert.is(err.statusCode, 404);
+		})
+		assert.is(res, undefined)
+	}
+	finally {
+		server.close();
+	}
+})
+
+basic('should not handle WebSocket requests', async () => {
+	let server = utils.http();
+
+	try {
+		// mock a websocket upgrade request
+		const headers = {'Upgrade': 'websocket' }
+		let res = await server.send('GET', '/contact', { headers }).catch(err => {
+			assert.is(err.statusCode, 404);
+		})
+		assert.is(res, undefined)
+	}
+	finally {
+		server.close();
+	}
+})
+
 basic('should return the file if found', async () => {
 	let server = utils.http();