diff --git a/.changeset/happy-ties-rule.md b/.changeset/happy-ties-rule.md
new file mode 100644
index 000000000..45b007a08
--- /dev/null
+++ b/.changeset/happy-ties-rule.md
@@ -0,0 +1,5 @@
+---
+"druxt-menu": minor
+---
+
+feat(#684): added druxtMenu/flushEntities Vuex mutation.
diff --git a/packages/menu/src/components/DruxtMenu.vue b/packages/menu/src/components/DruxtMenu.vue
index fce0aa976..4aaecb12a 100644
--- a/packages/menu/src/components/DruxtMenu.vue
+++ b/packages/menu/src/components/DruxtMenu.vue
@@ -222,6 +222,7 @@ export default {
   mounted() {
     // If logged in and statically generated, re-fetch the menu.
     if (this?.$auth?.loggedIn && this?.$store?.app?.context?.isStatic) {
+      this.$store.commit('druxtMenu/flushEntities', { prefix: this.lang })
       const settings = this.$options.druxt.settings(this, this.component.settings)
       this.$options.druxt.fetchData.call(this, settings)
     }
diff --git a/packages/menu/src/stores/menu.js b/packages/menu/src/stores/menu.js
index 24c0f99e6..b83dfaeb8 100644
--- a/packages/menu/src/stores/menu.js
+++ b/packages/menu/src/stores/menu.js
@@ -49,7 +49,21 @@ const DruxtMenuStore = ({ store }) => {
           const entity = entities[index]
           Vue.set(state.entities[prefix], entity.id, entity)
         }
-      }
+      },
+
+      /**
+       * @name flushEntities
+       * @mutator {object} flushEntities=entities Removes JSON:API menu item entities from the Vuex state object.
+       * @param {flushEntitiesContext} context
+       *
+       * @example @lang js
+       * // Flush all menu entities.
+       * this.$store.commit('druxt/flushCollection', {})
+       */
+      flushEntities (state, { prefix }) {
+        if (!prefix || typeof state.entities !== 'object') Vue.set(state, 'entities', {})
+        if (prefix) Vue.set(state.entities, prefix, {})
+      },
     },
 
     /**
@@ -120,3 +134,16 @@ export { DruxtMenuStore }
  * @typedef {object} State
  * @property {object} entities - The Drupal JSON:API Menu Item entities.
  */
+
+/**
+ * Parameters for the `flushEntities` mutation.
+ *
+ * @typedef {object} flushEntitiesContext
+ *
+ * @param {string} [prefix] - (Optional) The JSON:API endpoint prefix or langcode.
+ *
+ * @example @lang js
+ * {
+ *   prefix: 'en'
+ * }
+ */
diff --git a/packages/menu/test/stores/menu.test.js b/packages/menu/test/stores/menu.test.js
index fa47e805f..79847b3ba 100644
--- a/packages/menu/test/stores/menu.test.js
+++ b/packages/menu/test/stores/menu.test.js
@@ -33,4 +33,22 @@ describe('DruxtStore', () => {
     expect(store.$druxtMenu.get).toHaveBeenCalledWith('main', { test: true }, undefined)
     store.dispatch('druxtMenu/get', 'name')
   })
+
+  test('AddEntities', async () => {
+    expect(store.state.druxtMenu.entities).toStrictEqual({})
+    store.commit('druxtMenu/addEntities', { entities: [{ id: 'test' }] })
+    expect(Object.entries(store.state.druxtMenu.entities[undefined]).length).toBe(1)
+    expect(store.state.druxtMenu.entities[undefined].test).toStrictEqual({ id: 'test' })
+  })
+
+  test('flushEntities', async () => {
+    expect(store.state.druxtMenu.entities).toStrictEqual({})
+    store.commit('druxtMenu/addEntities', { entities: [{ id: 'test' }] })
+    store.commit('druxtMenu/addEntities', { entities: [{ id: 'test2' }], prefix: 'es' })
+    expect(Object.entries(store.state.druxtMenu.entities[undefined]).length).toBe(1)
+    store.commit('druxtMenu/flushEntities', { prefix: 'undefined' })
+    expect(Object.entries(store.state.druxtMenu.entities[undefined]).length).toBe(0)
+    store.commit('druxtMenu/flushEntities', {})
+    expect(Object.entries(store.state.druxtMenu.entities).length).toBe(0)
+  })
 })