diff --git a/feature-policy/feature-policy-for-sandbox/resources/helper.js b/feature-policy/feature-policy-for-sandbox/resources/helper.js
index 0d82811bcee613..09a8aa7846cd72 100644
--- a/feature-policy/feature-policy-for-sandbox/resources/helper.js
+++ b/feature-policy/feature-policy-for-sandbox/resources/helper.js
@@ -3,13 +3,18 @@ const all_features = document.featurePolicy.allowedFeatures();
 
 // 'popups' is nonsensical in this test and it is not possible to test 'scripts'
 // within this test model.
-const ignore_features = ["popups", "scripts"];
+const ignore_features_for_auxilary_context = ["popups", "scripts"];
+
+// Feature-policies that represent specific sandbox flags.
+const sandbox_features = [
+    "forms", "modals", "orientation-lock", "pointer-lock", "popups",
+    "presentation", "scripts", "top-navigation"];
 
 // TODO(ekaramad): Figure out different inheritance requirements for different
 // policies.
 // Features which will be tested for propagation to auxiliary contexts.
 const features_that_propagate = all_features.filter(
-    (feature) => !ignore_features.includes(feature));
+    (feature) => !ignore_features_for_auxilary_context.includes(feature));
 
 var last_feature_message = null;
 var on_new_feature_callback = null;
@@ -29,10 +34,28 @@ function add_iframe(options) {
   });
 }
 
+// Resolves after |c| animation frames.
+function wait_for_raf_count(c) {
+  let count = c;
+  let callback = null;
+  function on_raf() {
+    if (--count === 0) {
+      callback();
+      return;
+    }
+    window.requestAnimationFrame(on_raf);
+  }
+  return new Promise( r => {
+    callback = r;
+    window.requestAnimationFrame(on_raf);
+  });
+}
+
 // Returns a promise which is resolved with the next/already received message
 // with feature update for |feature|. The resolved value is the state of the
-// feature |feature|.
-function feature_update(feature) {
+// feature |feature|. If |optional_timeout| is provided, after the given delay
+// (in terms of rafs) the promise is resolved with false.
+function feature_update(feature, optional_timeout_rafs) {
   function reset_for_next_update() {
     return new Promise((r) => {
       const state = last_feature_message.state;
@@ -43,6 +66,13 @@ function feature_update(feature) {
   if (last_feature_message && last_feature_message.feature === feature)
     return reset_for_next_update();
 
+  if (optional_timeout_rafs) {
+    wait_for_raf_count(optional_timeout_rafs).then (() => {
+      last_feature_message = {state: false};
+      on_new_feature_callback();
+    });
+  }
+
   return new Promise((r) => on_new_feature_callback = r)
             .then(() => reset_for_next_update());
 }
diff --git a/feature-policy/feature-policy-for-sandbox/sandbox-policies-in-allow-attribute.html b/feature-policy/feature-policy-for-sandbox/sandbox-policies-in-allow-attribute.html
new file mode 100644
index 00000000000000..a29d43e5fccabe
--- /dev/null
+++ b/feature-policy/feature-policy-for-sandbox/sandbox-policies-in-allow-attribute.html
@@ -0,0 +1,46 @@
+<!DOCTYPE html>
+<head>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+</head>
+<body>
+<div id="iframe-embedder"></div>
+<script src="./resources/helper.js"></script>
+<script>
+'use strict';
+
+const iframe_src = "/feature-policy/feature-policy-for-sandbox/resources/window_opener.html";
+
+promise_test( async () => {
+  for (const feature of sandbox_features) {
+    // For the test to work correctly we need "scripts";
+    const sandbox_flags = feature === "scripts" ? "" : "allow-scripts";
+    const iframe = await add_iframe(
+        {src: iframe_src, allow: `${feature} *`, sandbox: sandbox_flags});
+    iframe.contentWindow.postMessage({type: "feature", feature: feature}, "*");
+    const iframe_state = await feature_update(feature);
+    assert_true(iframe_state,
+                `'${feature}' should not be disabled in <iframe>.'`);
+    iframe.parentElement.removeChild(iframe);
+  }
+}, "Verify that when a sandbox related feature is enabled in 'allow' then " +
+   " the feature will be enabled regardless of sandbox attribute's value.");
+
+promise_test( async() => {
+  for (const feature of sandbox_features) {
+    const sandbox_flags = `allow-${feature} allow-scripts`;
+    const iframe = await add_iframe(
+        {src: iframe_src, allow: `${feature} 'none'`, sandbox: sandbox_flags});
+    iframe.contentWindow.postMessage({type: "feature", feature: feature}, "*");
+    // 'scripts' will block running code in the subframe and no update can be
+    // sent. A timeout determines the feature is disabled.
+    const timeout = (feature === "scripts") ? 10 : false;
+    const iframe_state = await feature_update(feature, timeout);
+    assert_false(iframe_state,
+                `'${feature}' should be disabled in <iframe>.'`);
+    iframe.parentElement.removeChild(iframe);
+  }
+}, "Verify that when a sandbox related feature is disabled in 'allow' then " +
+   " the feature will be disabled regardless of sandbox attribute's value.");
+</script>
+</body>
\ No newline at end of file
