diff --git a/.changeset/stupid-elephants-invent.md b/.changeset/stupid-elephants-invent.md
new file mode 100644
index 0000000000..11b87a667d
--- /dev/null
+++ b/.changeset/stupid-elephants-invent.md
@@ -0,0 +1,5 @@
+---
+'@backstage/test-utils': patch
+---
+
+Store the namespaced bucket storage for each instance that was created with `MockStorage.create()` instead of global variable.
diff --git a/packages/test-utils/src/testUtils/apis/StorageApi/MockStorageApi.test.ts b/packages/test-utils/src/testUtils/apis/StorageApi/MockStorageApi.test.ts
index fabfa989e2..a3028f8b57 100644
--- a/packages/test-utils/src/testUtils/apis/StorageApi/MockStorageApi.test.ts
+++ b/packages/test-utils/src/testUtils/apis/StorageApi/MockStorageApi.test.ts
@@ -13,8 +13,8 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import { MockStorageApi } from './MockStorageApi';
 import { StorageApi } from '@backstage/core-plugin-api';
+import { MockStorageApi } from './MockStorageApi';
 
 describe('WebStorage Storage API', () => {
   const createMockStorage = (): StorageApi => {
@@ -124,7 +124,7 @@ describe('WebStorage Storage API', () => {
     expect(secondStorage.get(keyName)).toBe('deerp');
   });
 
-  it('should not clash with other namesapces when creating buckets', async () => {
+  it('should not clash with other namespaces when creating buckets', async () => {
     const rootStorage = createMockStorage();
 
     // when getting key test2 it will translate to /profile/something/deep/test2
@@ -139,4 +139,17 @@ describe('WebStorage Storage API', () => {
 
     expect(secondStorage.get('deep/test2')).toBe(undefined);
   });
+
+  it('should not reuse storage instances between different rootStorages', async () => {
+    const rootStorage1 = createMockStorage();
+    const rootStorage2 = createMockStorage();
+
+    const firstStorage = rootStorage1.forBucket('something');
+    const secondStorage = rootStorage2.forBucket('something');
+
+    await firstStorage.set('test2', true);
+
+    expect(firstStorage.get('test2')).toBe(true);
+    expect(secondStorage.get('test2')).toBe(undefined);
+  });
 });
diff --git a/packages/test-utils/src/testUtils/apis/StorageApi/MockStorageApi.ts b/packages/test-utils/src/testUtils/apis/StorageApi/MockStorageApi.ts
index 9f21b4e4c8..ab5d26afc5 100644
--- a/packages/test-utils/src/testUtils/apis/StorageApi/MockStorageApi.ts
+++ b/packages/test-utils/src/testUtils/apis/StorageApi/MockStorageApi.ts
@@ -23,29 +23,37 @@ import ObservableImpl from 'zen-observable';
 
 export type MockStorageBucket = { [key: string]: any };
 
-const bucketStorageApis = new Map<string, MockStorageApi>();
-
 export class MockStorageApi implements StorageApi {
   private readonly namespace: string;
   private readonly data: MockStorageBucket;
+  private readonly bucketStorageApis: Map<string, MockStorageApi>;
 
-  private constructor(namespace: string, data?: MockStorageBucket) {
+  private constructor(
+    namespace: string,
+    bucketStorageApis: Map<string, MockStorageApi>,
+    data?: MockStorageBucket,
+  ) {
     this.namespace = namespace;
+    this.bucketStorageApis = bucketStorageApis;
     this.data = { ...data };
   }
 
   static create(data?: MockStorageBucket) {
-    return new MockStorageApi('', data);
+    return new MockStorageApi('', new Map(), data);
   }
 
   forBucket(name: string): StorageApi {
-    if (!bucketStorageApis.has(name)) {
-      bucketStorageApis.set(
+    if (!this.bucketStorageApis.has(name)) {
+      this.bucketStorageApis.set(
         name,
-        new MockStorageApi(`${this.namespace}/${name}`, this.data),
+        new MockStorageApi(
+          `${this.namespace}/${name}`,
+          this.bucketStorageApis,
+          this.data,
+        ),
       );
     }
-    return bucketStorageApis.get(name)!;
+    return this.bucketStorageApis.get(name)!;
   }
 
   get<T>(key: string): T | undefined {