diff --git a/web-based-payment-handler/app-reject-errors.js b/web-based-payment-handler/app-reject-errors.js
new file mode 100644
index 00000000000000..3d2b30e96d2877
--- /dev/null
+++ b/web-based-payment-handler/app-reject-errors.js
@@ -0,0 +1,48 @@
+/**
+ * A payment handler that opens a window and allows the user to trigger
+ * different types of promise rejections for testing error propagation.
+ */
+
+let resolver = null;
+let rejecter = null;
+let activeMethodName = null;
+
+self.addEventListener('canmakepayment', event => {
+  event.respondWith(true);
+});
+
+self.addEventListener('message', msgEvent => {
+  if (!resolver || !rejecter) return;
+
+  if (msgEvent.data === 'success') {
+    resolver({
+      methodName: activeMethodName,
+      details: {status: 'success'},
+    });
+  } else if (msgEvent.data === 'reject-operation-error') {
+    rejecter(new DOMException('Reject with OperationError', 'OperationError'));
+  } else if (msgEvent.data === 'reject-syntax-error') {
+    rejecter(new DOMException('Reject with SyntaxError', 'SyntaxError'));
+  } else {
+    return; // Message not for us.
+  }
+
+  resolver = null;
+  rejecter = null;
+  activeMethodName = null;
+});
+
+self.addEventListener('paymentrequest', event => {
+  activeMethodName = event.methodData[0].supportedMethods;
+  event.respondWith(new Promise((resolve, reject) => {
+    resolver = resolve;
+    rejecter = reject;
+
+    event.openWindow('payment-app/reject-errors.html').catch(err => {
+      resolver = null;
+      rejecter = null;
+      activeMethodName = null;
+      reject(err);
+    });
+  }));
+});
diff --git a/web-based-payment-handler/payment-app/reject-errors.html b/web-based-payment-handler/payment-app/reject-errors.html
new file mode 100644
index 00000000000000..4f7361ee52f3fe
--- /dev/null
+++ b/web-based-payment-handler/payment-app/reject-errors.html
@@ -0,0 +1,18 @@
+<!doctype html>
+<meta charset="utf-8">
+<title>Reject Error Payment App</title>
+<p>Please click one of the buttons below to complete or reject the payment.</p>
+<button id="success">Authorize (Success)</button>
+<button id="reject-operation-error">Reject with OperationError</button>
+<button id="reject-syntax-error">Reject with SyntaxError</button>
+
+<script>
+  for (const id of ['success', 'reject-operation-error', 'reject-syntax-error']) {
+    document.getElementById(id).onclick = () => {
+      if (navigator.serviceWorker.controller) {
+        navigator.serviceWorker.controller.postMessage(id);
+      }
+      window.close();
+    };
+  }
+</script>
diff --git a/web-based-payment-handler/payment-request-reject-errors-manifest.json b/web-based-payment-handler/payment-request-reject-errors-manifest.json
new file mode 100644
index 00000000000000..ea6c372f3988c3
--- /dev/null
+++ b/web-based-payment-handler/payment-request-reject-errors-manifest.json
@@ -0,0 +1,15 @@
+{
+  "default_applications": ["payment-request-reject-errors-manifest.json"],
+  "name": "Reject Errors Payment Handler",
+  "icons": [
+    {
+      "src": "/images/rgrg-256x256.png",
+      "sizes": "256x256",
+      "type": "image/png"
+    }
+  ],
+  "serviceworker": {
+    "src": "app-reject-errors.js",
+    "scope": "./"
+  }
+}
diff --git a/web-based-payment-handler/payment-request-reject-errors-manifest.json.headers b/web-based-payment-handler/payment-request-reject-errors-manifest.json.headers
new file mode 100644
index 00000000000000..88ddbb0a5e8c57
--- /dev/null
+++ b/web-based-payment-handler/payment-request-reject-errors-manifest.json.headers
@@ -0,0 +1 @@
+Link: </web-based-payment-handler/payment-request-reject-errors-manifest.json>; rel="payment-method-manifest"
diff --git a/web-based-payment-handler/payment-request-reject-operation-error-manual.https.html b/web-based-payment-handler/payment-request-reject-operation-error-manual.https.html
new file mode 100644
index 00000000000000..7a9575c8b04e08
--- /dev/null
+++ b/web-based-payment-handler/payment-request-reject-operation-error-manual.https.html
@@ -0,0 +1,37 @@
+<!doctype html>
+<meta charset="utf-8">
+<title>Manual Tests for rejecting respondWith with errors</title>
+<link rel="help" href="https://w3c.github.io/web-based-payment-handler/#the-paymentrequestevent">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/resources/testdriver.js"></script>
+<script src="/resources/testdriver-vendor.js"></script>
+<p>This test verifies that if a payment app rejects the promise passed to <code>respondWith</code> with an <code>OperationError</code>, the original <code>PaymentRequest.show()</code> call also rejects with an <code>OperationError</code>. For other error types, it should still reject with an <code>AbortError</code>.</p>
+<p>Please follow these instructions:</p>
+<ol>
+  <li>For the first test (<b>OperationError</b>), click "Reject with OperationError".</li>
+  <li>For the second test (<b>SyntaxError</b>), click "Reject with SyntaxError".</li>
+</ol>
+
+<script>
+  const methodName = window.location.origin + '/web-based-payment-handler/'
+      + 'payment-request-reject-errors-manifest.json';
+
+  promise_test(async t => {
+    await test_driver.bless('invoking a payment app for OperationError');
+    const request = new PaymentRequest([{supportedMethods: methodName}], {
+      total: {label: 'Total', amount: {currency: 'USD', value: '0.01'}},
+    });
+    // show() should reject with the SAME error if it's OperationError.
+    await promise_rejects_dom(t, 'OperationError', request.show());
+  }, 'If a payment app rejects with OperationError, show() rejects with OperationError');
+
+  promise_test(async t => {
+    await test_driver.bless('invoking a payment app for SyntaxError');
+    const request = new PaymentRequest([{supportedMethods: methodName}], {
+      total: {label: 'Total', amount: {currency: 'USD', value: '0.01'}},
+    });
+    // show() should reject with AbortError for other error types.
+    await promise_rejects_dom(t, 'AbortError', request.show());
+  }, 'If a payment app rejects with SyntaxError, show() rejects with AbortError');
+</script>
