diff --git a/ts/components/conversation/conversation-details/ConversationDetails.tsx b/ts/components/conversation/conversation-details/ConversationDetails.tsx
index 4d74f69e2..df6a8cb9e 100644
--- a/ts/components/conversation/conversation-details/ConversationDetails.tsx
+++ b/ts/components/conversation/conversation-details/ConversationDetails.tsx
@@ -44,7 +44,7 @@ import type {
   ReplaceAvatarActionType,
   SaveAvatarToDiskActionType,
 } from '../../../types/Avatar';
-import { isMuted } from '../../../util/isMuted';
+import { isConversationMuted } from '../../../util/isConversationMuted';
 
 enum ModalState {
   NothingOpen,
@@ -305,7 +305,7 @@ export const ConversationDetails: React.ComponentType<Props> = ({
       throw missingCaseError(modalState);
   }
 
-  const isConversationMuted = isMuted(conversation.muteExpiresAt);
+  const isMuted = isConversationMuted(conversation);
 
   return (
     <div className="conversation-details-panel">
@@ -348,11 +348,9 @@ export const ConversationDetails: React.ComponentType<Props> = ({
           </>
         )}
         <Button
-          icon={
-            isConversationMuted ? ButtonIconType.muted : ButtonIconType.unmuted
-          }
+          icon={isMuted ? ButtonIconType.muted : ButtonIconType.unmuted}
           onClick={() => {
-            if (isConversationMuted) {
+            if (isMuted) {
               setModalState(ModalState.UnmuteNotifications);
             } else {
               setModalState(ModalState.MuteNotifications);
@@ -360,7 +358,7 @@ export const ConversationDetails: React.ComponentType<Props> = ({
           }}
           variant={ButtonVariant.Details}
         >
-          {isConversationMuted ? i18n('unmute') : i18n('mute')}
+          {isMuted ? i18n('unmute') : i18n('mute')}
         </Button>
         <Button
           icon={ButtonIconType.search}
diff --git a/ts/components/conversation/conversation-details/ConversationNotificationsSettings.tsx b/ts/components/conversation/conversation-details/ConversationNotificationsSettings.tsx
index bec9309a6..07bbc2929 100644
--- a/ts/components/conversation/conversation-details/ConversationNotificationsSettings.tsx
+++ b/ts/components/conversation/conversation-details/ConversationNotificationsSettings.tsx
@@ -10,7 +10,7 @@ import { PanelSection } from './PanelSection';
 import { PanelRow } from './PanelRow';
 import { ConversationDetailsIcon, IconType } from './ConversationDetailsIcon';
 import { Select } from '../../Select';
-import { isMuted } from '../../../util/isMuted';
+import { isConversationMuted } from '../../../util/isConversationMuted';
 import { getMuteOptions } from '../../../util/getMuteOptions';
 import { parseIntOrThrow } from '../../../util/parseIntOrThrow';
 import { useUniqueId } from '../../../hooks/useUniqueId';
@@ -40,7 +40,7 @@ export const ConversationNotificationsSettings: FunctionComponent<
   const mentionsSelectId = useUniqueId();
   const muteOptions = useMemo(
     () => [
-      ...(isMuted(muteExpiresAt)
+      ...(isConversationMuted({ muteExpiresAt })
         ? []
         : [
             {
diff --git a/ts/models/conversations.ts b/ts/models/conversations.ts
index 05d2558a4..dca91eecd 100644
--- a/ts/models/conversations.ts
+++ b/ts/models/conversations.ts
@@ -44,7 +44,7 @@ import type {
 import type { MessageModel } from './messages';
 import { getContact } from '../messages/helpers';
 import { strictAssert } from '../util/assert';
-import { isMuted } from '../util/isMuted';
+import { isConversationMuted } from '../util/isConversationMuted';
 import { isConversationSMSOnly } from '../util/isConversationSMSOnly';
 import { isConversationUnregistered } from '../util/isConversationUnregistered';
 import { missingCaseError } from '../util/missingCaseError';
@@ -5203,7 +5203,7 @@ export class ConversationModel extends window.Backbone
   }
 
   isMuted(): boolean {
-    return isMuted(this.get('muteExpiresAt'));
+    return isConversationMuted(this.attributes);
   }
 
   async notify(
diff --git a/ts/test-both/util/isConversationMuted_test.ts b/ts/test-both/util/isConversationMuted_test.ts
new file mode 100644
index 000000000..8c550ebd2
--- /dev/null
+++ b/ts/test-both/util/isConversationMuted_test.ts
@@ -0,0 +1,23 @@
+// Copyright 2020-2022 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { assert } from 'chai';
+
+import { isConversationMuted } from '../../util/isConversationMuted';
+
+describe('isConversationMuted', () => {
+  it('returns false if passed an undefined expiry time', () => {
+    assert.isFalse(isConversationMuted({}));
+    assert.isFalse(isConversationMuted({ muteExpiresAt: undefined }));
+  });
+
+  it('returns false if passed a date in the past', () => {
+    assert.isFalse(isConversationMuted({ muteExpiresAt: 0 }));
+    assert.isFalse(isConversationMuted({ muteExpiresAt: Date.now() - 123 }));
+  });
+
+  it('returns true if passed a date in the future', () => {
+    assert.isTrue(isConversationMuted({ muteExpiresAt: Date.now() + 123 }));
+    assert.isTrue(isConversationMuted({ muteExpiresAt: Date.now() + 123456 }));
+  });
+});
diff --git a/ts/test-node/util/isMuted_test.ts b/ts/test-node/util/isMuted_test.ts
deleted file mode 100644
index c937f1c8d..000000000
--- a/ts/test-node/util/isMuted_test.ts
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright 2020 Signal Messenger, LLC
-// SPDX-License-Identifier: AGPL-3.0-only
-
-import { assert } from 'chai';
-
-import { isMuted } from '../../util/isMuted';
-
-describe('isMuted', () => {
-  it('returns false if passed undefined', () => {
-    assert.isFalse(isMuted(undefined));
-  });
-
-  it('returns false if passed a date in the past', () => {
-    assert.isFalse(isMuted(0));
-    assert.isFalse(isMuted(Date.now() - 123));
-  });
-
-  it('returns false if passed a date in the future', () => {
-    assert.isTrue(isMuted(Date.now() + 123));
-    assert.isTrue(isMuted(Date.now() + 123456));
-  });
-});
diff --git a/ts/util/getMuteOptions.ts b/ts/util/getMuteOptions.ts
index 5b42c4185..30be76b21 100644
--- a/ts/util/getMuteOptions.ts
+++ b/ts/util/getMuteOptions.ts
@@ -1,10 +1,10 @@
-// Copyright 2020-2021 Signal Messenger, LLC
+// Copyright 2020-2022 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
 import * as durations from './durations';
 import type { LocalizerType } from '../types/Util';
 import { getMutedUntilText } from './getMutedUntilText';
-import { isMuted } from './isMuted';
+import { isConversationMuted } from './isConversationMuted';
 
 export type MuteOption = {
   name: string;
@@ -17,7 +17,7 @@ export function getMuteOptions(
   i18n: LocalizerType
 ): Array<MuteOption> {
   return [
-    ...(isMuted(muteExpiresAt)
+    ...(muteExpiresAt && isConversationMuted({ muteExpiresAt })
       ? [
           {
             name: getMutedUntilText(muteExpiresAt, i18n),
diff --git a/ts/util/isConversationMuted.ts b/ts/util/isConversationMuted.ts
new file mode 100644
index 000000000..2ccb75490
--- /dev/null
+++ b/ts/util/isConversationMuted.ts
@@ -0,0 +1,9 @@
+// Copyright 2020-2022 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import type { ConversationAttributesType } from '../model-types.d';
+
+export const isConversationMuted = ({
+  muteExpiresAt,
+}: Readonly<Pick<ConversationAttributesType, 'muteExpiresAt'>>): boolean =>
+  Boolean(muteExpiresAt && Date.now() < muteExpiresAt);
diff --git a/ts/util/isMuted.ts b/ts/util/isMuted.ts
deleted file mode 100644
index ecdf8f854..000000000
--- a/ts/util/isMuted.ts
+++ /dev/null
@@ -1,8 +0,0 @@
-// Copyright 2020-2021 Signal Messenger, LLC
-// SPDX-License-Identifier: AGPL-3.0-only
-
-export function isMuted(
-  muteExpiresAt: undefined | number
-): muteExpiresAt is number {
-  return Boolean(muteExpiresAt && Date.now() < muteExpiresAt);
-}