diff --git a/shared-storage/permissions-policy-default.tentative.https.sub.html b/shared-storage/permissions-policy-default.tentative.https.sub.html
new file mode 100644
index 00000000000000..f055ae0421f6c9
--- /dev/null
+++ b/shared-storage/permissions-policy-default.tentative.https.sub.html
@@ -0,0 +1,29 @@
+<!doctype html>
+<body>
+  <script src=/resources/testharness.js></script>
+  <script src=/resources/testharnessreport.js></script>
+  <script src=/permissions-policy/resources/permissions-policy.js></script>
+  <script src="/shared-storage/resources/util.js"></script>
+  <script>
+    'use strict';
+    const same_origin_src = '/shared-storage/resources/permissions-policy-helper.html';
+    const cross_origin_src = 'https://{{domains[www]}}:{{ports[https][0]}}' +
+      same_origin_src;
+    const header = 'Default permissions policy';
+
+    promise_test(async t => {
+      const allowed = await AreSharedStorageMethodsAllowedByPermissionsPolicy();
+      assert_true(allowed);
+    }, header + ' allows sharedStorage in the current page.');
+
+    async_test(t => {
+      test_feature_availability('shared-storage', t, same_origin_src,
+          expect_feature_available_default);
+    }, header + ' allows sharedStorage in same-origin iframes.');
+
+    async_test(t => {
+      test_feature_availability('shared-storage', t, cross_origin_src,
+          expect_feature_available_default);
+    }, header + ' allows sharedStorage in cross-origin iframes.');
+  </script>
+</body>
diff --git a/shared-storage/permissions-policy-none.tentative.https.sub.html b/shared-storage/permissions-policy-none.tentative.https.sub.html
new file mode 100644
index 00000000000000..7154061d50abad
--- /dev/null
+++ b/shared-storage/permissions-policy-none.tentative.https.sub.html
@@ -0,0 +1,29 @@
+<!doctype html>
+<body>
+  <script src=/resources/testharness.js></script>
+  <script src=/resources/testharnessreport.js></script>
+  <script src=/permissions-policy/resources/permissions-policy.js></script>
+  <script src="/shared-storage/resources/util.js"></script>
+  <script>
+    'use strict';
+    const same_origin_src = '/shared-storage/resources/permissions-policy-helper.html';
+    const cross_origin_src = 'https://{{domains[www]}}:{{ports[https][0]}}' +
+      same_origin_src;
+    const header = 'permissions policy header shared-storage=()';
+
+    promise_test(async t => {
+      const allowed = await AreSharedStorageMethodsAllowedByPermissionsPolicy();
+      assert_false(allowed);
+    }, header + ' disallows sharedStorage in the current page.');
+
+    async_test(t => {
+      test_feature_availability('shared-storage', t, same_origin_src,
+          expect_feature_unavailable_default);
+    }, header + ' disallows sharedStorage in same-origin iframes.');
+
+    async_test(t => {
+      test_feature_availability('shared-storage', t, cross_origin_src,
+          expect_feature_unavailable_default);
+    }, header + ' disallows sharedStorage in cross-origin iframes.');
+  </script>
+</body>
diff --git a/shared-storage/permissions-policy-none.tentative.https.sub.html.headers b/shared-storage/permissions-policy-none.tentative.https.sub.html.headers
new file mode 100644
index 00000000000000..9903f7c578df6a
--- /dev/null
+++ b/shared-storage/permissions-policy-none.tentative.https.sub.html.headers
@@ -0,0 +1 @@
+Permissions-Policy: shared-storage=()
diff --git a/shared-storage/permissions-policy-self.tentative.https.sub.html b/shared-storage/permissions-policy-self.tentative.https.sub.html
new file mode 100644
index 00000000000000..bde32a5c306602
--- /dev/null
+++ b/shared-storage/permissions-policy-self.tentative.https.sub.html
@@ -0,0 +1,29 @@
+<!doctype html>
+<body>
+  <script src=/resources/testharness.js></script>
+  <script src=/resources/testharnessreport.js></script>
+  <script src=/permissions-policy/resources/permissions-policy.js></script>
+  <script src="/shared-storage/resources/util.js"></script>
+  <script>
+    'use strict';
+    const same_origin_src = '/shared-storage/resources/permissions-policy-helper.html';
+    const cross_origin_src = 'https://{{domains[www]}}:{{ports[https][0]}}' +
+      same_origin_src;
+    const header = 'permissions policy header shared-storage=(self)';
+
+    promise_test(async t => {
+      const allowed = await AreSharedStorageMethodsAllowedByPermissionsPolicy();
+      assert_true(allowed);
+    }, header + ' allows sharedStorage in the current page.');
+
+    async_test(t => {
+      test_feature_availability('shared-storage', t, same_origin_src,
+          expect_feature_available_default);
+    }, header + ' allows sharedStorage in same-origin iframes.');
+
+    async_test(t => {
+      test_feature_availability('shared-storage', t, cross_origin_src,
+          expect_feature_unavailable_default);
+    }, header + ' disallows sharedStorage in cross-origin iframes.');
+  </script>
+</body>
diff --git a/shared-storage/permissions-policy-self.tentative.https.sub.html.headers b/shared-storage/permissions-policy-self.tentative.https.sub.html.headers
new file mode 100644
index 00000000000000..36c95f2b087ba0
--- /dev/null
+++ b/shared-storage/permissions-policy-self.tentative.https.sub.html.headers
@@ -0,0 +1 @@
+Permissions-Policy: shared-storage=(self)
diff --git a/shared-storage/resources/permissions-policy-helper.html b/shared-storage/resources/permissions-policy-helper.html
new file mode 100644
index 00000000000000..d87092aad1d2ef
--- /dev/null
+++ b/shared-storage/resources/permissions-policy-helper.html
@@ -0,0 +1,18 @@
+<!doctype html>
+<body>
+  <script src="/resources/testharness.js"></script>
+  <script src="/resources/testharnessreport.js"></script>
+  <script src="/shared-storage/resources/util.js"></script>
+  <script>
+  'use strict';
+
+  window.onload = async function() {
+    if (await AreSharedStorageMethodsAllowedByPermissionsPolicy()) {
+      parent.postMessage({ type: 'availability-result', enabled: true }, '*');
+      return;
+    }
+
+    parent.postMessage({ type: 'availability-result', enabled: false }, '*');
+  }
+  </script>
+</body>
diff --git a/shared-storage/resources/simple-module.js b/shared-storage/resources/simple-module.js
new file mode 100644
index 00000000000000..ad9a93a7c160f0
--- /dev/null
+++ b/shared-storage/resources/simple-module.js
@@ -0,0 +1 @@
+'use strict';
diff --git a/shared-storage/resources/util.js b/shared-storage/resources/util.js
new file mode 100644
index 00000000000000..4dea9837646dc3
--- /dev/null
+++ b/shared-storage/resources/util.js
@@ -0,0 +1,69 @@
+'use strict';
+
+// Execute all shared storage methods and capture their errors. Return true if
+// the permissions policy allows all of them; return false if the permissions
+// policy disallows all of them. Precondition: only these two outcomes are
+// possible.
+async function AreSharedStorageMethodsAllowedByPermissionsPolicy() {
+  let permissionsPolicyDeniedCount = 0;
+  const errorMessage = 'The \"shared-storage\" Permissions Policy denied the method on window.sharedStorage.';
+
+  try {
+    await window.sharedStorage.worklet.addModule('/shared-storage/resources/simple-module.js');
+  } catch (e) {
+    assert_equals(e.message, errorMessage);
+    ++permissionsPolicyDeniedCount;
+  }
+
+  try {
+    await window.sharedStorage.run('operation');
+  } catch (e) {
+    assert_equals(e.message, errorMessage);
+    ++permissionsPolicyDeniedCount;
+  }
+
+  try {
+    // Run selectURL() with without addModule() and this should always fail.
+    // Check the error message to distinguish between the permissions policy
+    // error and the missing addModule() error.
+    await sharedStorage.selectURL("operation", [{url: "1.html"}]);
+    assert_unreached("did not fail");
+  } catch (e) {
+    if (e.message === errorMessage) {
+      ++permissionsPolicyDeniedCount;
+    }
+  }
+
+  try {
+    await window.sharedStorage.set('a', 'b');
+  } catch (e) {
+    assert_equals(e.message, errorMessage);
+    ++permissionsPolicyDeniedCount;
+  }
+
+  try {
+    await window.sharedStorage.append('a', 'b');
+  } catch (e) {
+    assert_equals(e.message, errorMessage);
+    ++permissionsPolicyDeniedCount;
+  }
+
+  try {
+    await window.sharedStorage.clear();
+  } catch (e) {
+    assert_equals(e.message, errorMessage);
+    ++permissionsPolicyDeniedCount;
+  }
+
+  try {
+    await window.sharedStorage.delete('a');
+  } catch (e) {
+    assert_equals(e.message, errorMessage);
+    ++permissionsPolicyDeniedCount;
+  }
+
+  if (permissionsPolicyDeniedCount === 0)
+    return true;
+
+  return false;
+}
\ No newline at end of file
