diff --git a/src/index.mjs b/src/index.mjs
index d4beeec..e6f953d 100644
--- a/src/index.mjs
+++ b/src/index.mjs
@@ -11,8 +11,10 @@ export default function(url, options) {
 
 		request.withCredentials = options.credentials=='include';
 
-		request.onload = () => {
-			resolve(response());
+		request.onreadystatechange = function() {
+			if(this.readyState === 4 && this.status !== 0) {
+				resolve(response());
+			}
 		};
 
 		request.onerror = reject;
diff --git a/test/index.js b/test/index.js
index 3a9e598..92f85b3 100644
--- a/test/index.js
+++ b/test/index.js
@@ -20,6 +20,7 @@ describe('unfetch', () => {
 				getAllResponseHeaders: jest.fn().mockReturnValue('X-Foo: bar\nX-Foo:baz'),
 				open: jest.fn(),
 				send: jest.fn(),
+				readyState: 4,
 				status: 200,
 				statusText: 'OK',
 				responseText: '{"a":"b"}',
@@ -60,10 +61,10 @@ describe('unfetch', () => {
 					expect(xhr.send).toHaveBeenCalledWith(null);
 				});
 
-			expect(xhr.onload).toEqual(expect.any(Function));
+			expect(xhr.onreadystatechange).toEqual(expect.any(Function));
 			expect(xhr.onerror).toEqual(expect.any(Function));
 
-			xhr.onload();
+			xhr.onreadystatechange();
 
 			return p;
 		});
@@ -76,7 +77,7 @@ describe('unfetch', () => {
 					expect(r.headers.get('X-foo')).toEqual('baz');
 				});
 
-			xhr.onload();
+			xhr.onreadystatechange();
 
 			return p;
 		});