diff --git a/packages/instantsearch-core/src/__tests__/instantsearch.test.tsx b/packages/instantsearch-core/src/__tests__/instantsearch.test.tsx
index 387bd3e6ea..b5a299092b 100644
--- a/packages/instantsearch-core/src/__tests__/instantsearch.test.tsx
+++ b/packages/instantsearch-core/src/__tests__/instantsearch.test.tsx
@@ -378,7 +378,7 @@ search.addWidgets([
 See https://www.algolia.com/doc/api-reference/widgets/configure/js/`);
   });
 
-  it("exposes helper's last results", async () => {
+  it("helper's results are null", async () => {
     const searchClient = createSearchClient();
 
     const search = new InstantSearch({
@@ -394,8 +394,7 @@ See https://www.algolia.com/doc/api-reference/widgets/configure/js/`);
 
     await wait(0);
 
-    // could be null if we don't pretend the main helper is the one who searched
-    expect(search.helper!.lastResults).not.toBe(null);
+    expect(search.helper!.lastResults).toBe(null);
   });
 
   describe('insights middleware', () => {
@@ -822,9 +821,9 @@ describe('start', () => {
 
     await wait(0);
 
-    expect(
-      search.mainHelper!.searchOnlyWithDerivedHelpers
-    ).toHaveBeenCalledTimes(1);
+    expect(search.helper!.searchOnlyWithDerivedHelpers).toHaveBeenCalledTimes(
+      1
+    );
   });
 
   it('forwards the `initialUiState` to the main index', () => {
@@ -1004,7 +1003,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/instantsear
 `);
   });
 
-  it('keeps a mainHelper already set on the instance (Vue SSR)', () => {
+  it('keeps a helper already set on the instance (Vue SSR)', () => {
     const searchClient = createSearchClient();
     const instance = new InstantSearch({
       indexName: 'indexName',
@@ -1013,17 +1012,17 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/instantsear
 
     const helper = algoliasearchHelper(searchClient, '');
 
-    // explicitly setting the mainHelper before start is used to force render to
+    // explicitly setting the helper before start is used to force render to
     // happen before the results of the first search are done. We need to make
     // sure no extra helper is created, as that can cause certain things (like routing)
     // to be listening to the wrong helper.
-    instance.mainHelper = helper;
+    instance.helper = helper;
 
-    expect(instance.mainHelper).toBe(helper);
+    expect(instance.helper).toBe(helper);
 
     instance.start();
 
-    expect(instance.mainHelper).toBe(helper);
+    expect(instance.helper).toBe(helper);
   });
 
   it('no query for root if indexName is not given', async () => {
@@ -1122,7 +1121,7 @@ describe('dispose', () => {
     await wait(0);
 
     // Simulate a search
-    search.mainHelper!.search();
+    search.helper!.search();
 
     search.dispose();
 
@@ -1195,17 +1194,17 @@ describe('dispose', () => {
 
     search.start();
 
-    const mainHelper = search.mainHelper!;
+    const helper = search.helper!;
 
-    mainHelper.on('searchQueueEmpty', onEventName);
+    helper.on('searchQueueEmpty', onEventName);
 
-    mainHelper.emit('searchQueueEmpty');
+    helper.emit('searchQueueEmpty');
 
     expect(onEventName).toHaveBeenCalledTimes(1);
 
     search.dispose();
 
-    mainHelper.emit('searchQueueEmpty');
+    helper.emit('searchQueueEmpty');
 
     expect(onEventName).toHaveBeenCalledTimes(1);
   });
@@ -1240,7 +1239,7 @@ describe('dispose', () => {
     expect(onRender).toHaveBeenCalledTimes(2);
   });
 
-  it('removes the Helpers references', () => {
+  it('removes the helper references', () => {
     const search = new InstantSearch({
       indexName: 'indexName',
       searchClient: createSearchClient(),
@@ -1248,17 +1247,14 @@ describe('dispose', () => {
 
     search.start();
 
-    expect(search.mainHelper).not.toBe(null);
     expect(search.helper).not.toBe(null);
 
     search.dispose();
 
-    expect(search.mainHelper).toBe(null);
     expect(search.helper).toBe(null);
 
     search.start();
 
-    expect(search.mainHelper).not.toBe(null);
     expect(search.helper).not.toBe(null);
   });
 
@@ -1283,15 +1279,15 @@ describe('scheduleSearch', () => {
 
     search.start();
 
-    const mainHelperSearch = jest.spyOn(search.mainHelper!, 'search');
+    const helperSearch = jest.spyOn(search.helper!, 'search');
 
     search.scheduleSearch();
 
-    expect(mainHelperSearch).toHaveBeenCalledTimes(0);
+    expect(helperSearch).toHaveBeenCalledTimes(0);
 
     await wait(0);
 
-    expect(mainHelperSearch).toHaveBeenCalledTimes(1);
+    expect(helperSearch).toHaveBeenCalledTimes(1);
   });
 
   it('deduplicates the calls to the `search` method', async () => {
@@ -1304,18 +1300,18 @@ describe('scheduleSearch', () => {
 
     search.start();
 
-    const mainHelperSearch = jest.spyOn(search.mainHelper!, 'search');
+    const helperSearch = jest.spyOn(search.helper!, 'search');
 
     search.scheduleSearch();
     search.scheduleSearch();
     search.scheduleSearch();
     search.scheduleSearch();
 
-    expect(mainHelperSearch).toHaveBeenCalledTimes(0);
+    expect(helperSearch).toHaveBeenCalledTimes(0);
 
     await wait(0);
 
-    expect(mainHelperSearch).toHaveBeenCalledTimes(1);
+    expect(helperSearch).toHaveBeenCalledTimes(1);
   });
 });
 
@@ -1418,7 +1414,7 @@ describe('scheduleStalledRender', () => {
     castToJestMock(widget.render!).mockReset();
 
     // Trigger a new search
-    search.mainHelper!.search();
+    search.helper!.search();
 
     // search starts
     await wait(0);
@@ -1456,10 +1452,10 @@ describe('scheduleStalledRender', () => {
     castToJestMock(widget.render!).mockClear();
 
     // Trigger multiple searches
-    search.mainHelper!.search();
-    search.mainHelper!.search();
-    search.mainHelper!.search();
-    search.mainHelper!.search();
+    search.helper!.search();
+    search.helper!.search();
+    search.helper!.search();
+    search.helper!.search();
 
     await wait(0);
 
@@ -1507,7 +1503,7 @@ describe('scheduleStalledRender', () => {
     );
 
     // Trigger a new search
-    search.mainHelper!.search();
+    search.helper!.search();
 
     expect(widget.render).toHaveBeenCalledTimes(1);
     castToJestMock(widget.render!).mockClear();
diff --git a/packages/instantsearch-core/src/connectors/__tests__/connectGeoSearch.test.ts b/packages/instantsearch-core/src/connectors/__tests__/connectGeoSearch.test.ts
index 6a41ad6cb9..711356b85c 100644
--- a/packages/instantsearch-core/src/connectors/__tests__/connectGeoSearch.test.ts
+++ b/packages/instantsearch-core/src/connectors/__tests__/connectGeoSearch.test.ts
@@ -73,7 +73,7 @@ describe('connectGeoSearch', () => {
     const widget = customGeoSearch({});
 
     const instantSearchInstance = createInstantSearch();
-    const helper = instantSearchInstance.mainHelper!;
+    const helper = instantSearchInstance.helper!;
 
     widget.init!(
       createInitOptions({
@@ -160,7 +160,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/geo-search/
     const widget = customGeoSearch({});
 
     const instantSearchInstance = createInstantSearch();
-    const { mainHelper: helper } = instantSearchInstance;
+    const { helper } = instantSearchInstance;
 
     widget.init!(createInitOptions({ instantSearchInstance }));
 
diff --git a/packages/instantsearch-core/src/instantsearch.ts b/packages/instantsearch-core/src/instantsearch.ts
index b9a93dee37..d13cee3892 100644
--- a/packages/instantsearch-core/src/instantsearch.ts
+++ b/packages/instantsearch-core/src/instantsearch.ts
@@ -65,7 +65,6 @@ export class InstantSearch<
   onStateChange: InstantSearchOptions<TUiState>['onStateChange'] | null = null;
   future: NonNullable<InstantSearchOptions<TUiState>['future']>;
   helper: AlgoliaSearchHelper | null;
-  mainHelper: AlgoliaSearchHelper | null;
   mainIndex: IndexWidget;
   started: boolean;
   renderState: RenderState = {};
@@ -74,7 +73,7 @@ export class InstantSearch<
   _initialUiState: TUiState;
   _initialResults: InitialResults | null;
   _createURL: CreateURL<TUiState>;
-  _mainHelperSearch?: AlgoliaSearchHelper['search'];
+  _helperSearch?: AlgoliaSearchHelper['search'];
   _hasSearchWidget: boolean = false;
   _hasRecommendWidget: boolean = false;
   _insights: InstantSearchOptions['insights'];
@@ -150,7 +149,6 @@ See ${createDocumentationLink({
     this.future = future;
     this.indexName = indexName;
     this.helper = null;
-    this.mainHelper = null;
     this.mainIndex = index({
       indexName,
     });
@@ -296,11 +294,11 @@ See ${createDocumentationLink({
     // DerivedHelper scoped into the `index` widgets.
     // In Vue InstantSearch' hydrate, a main helper gets set before start, so
     // we need to respect this helper as a way to keep all listeners correct.
-    const mainHelper =
-      this.mainHelper ||
+    const helper =
+      this.helper ||
       algoliasearchHelper(this.client, this.indexName, undefined);
 
-    mainHelper.search = () => {
+    helper.search = () => {
       this.status = 'loading';
       this.scheduleRender(false);
 
@@ -315,19 +313,19 @@ See ${createDocumentationLink({
       // completely transparent for the rest of the codebase. Only this module
       // is impacted.
       if (this._hasSearchWidget) {
-        mainHelper.searchOnlyWithDerivedHelpers();
+        helper.searchOnlyWithDerivedHelpers();
       }
 
       if (this._hasRecommendWidget) {
-        mainHelper.recommend();
+        helper.recommend();
       }
 
-      return mainHelper;
+      return helper;
     };
 
     // Only the "main" Helper emits the `error` event vs the one for `search`
     // and `results` that are also emitted on the derived one.
-    mainHelper.on('error', (error) => {
+    helper.on('error', (error) => {
       if (!(error instanceof Error)) {
         // typescript lies here, error is in some cases { name: string, message: string }
         const err = error as Record<string, any>;
@@ -345,7 +343,7 @@ See ${createDocumentationLink({
       this.emit('error', this.error);
     });
 
-    this.mainHelper = mainHelper;
+    this.helper = helper;
 
     this.middleware.forEach(({ instance }) => {
       instance.subscribe();
@@ -359,7 +357,7 @@ See ${createDocumentationLink({
 
     if (this._initialResults) {
       hydrateSearchClient(this.client, this._initialResults);
-      hydrateRecommendCache(this.mainHelper, this._initialResults);
+      hydrateRecommendCache(this.helper, this._initialResults);
 
       const originalScheduleSearch = this.scheduleSearch;
       // We don't schedule a first search when initial results are provided
@@ -387,10 +385,6 @@ See ${createDocumentationLink({
       this.scheduleSearch();
     }
 
-    // Keep the previous reference for legacy purpose, some pattern use
-    // the direct Helper access `search.helper` (e.g multi-index).
-    this.helper = this.mainIndex.getHelper();
-
     // track we started the search if we add more widgets,
     // to init them directly after add
     this.started = true;
@@ -403,7 +397,7 @@ See ${createDocumentationLink({
     // added when `insights` is unset and the initial results possess `queryID`.
     // Any user-provided middleware will be added later and override this one.
     if (typeof this._insights === 'undefined') {
-      mainHelper.derivedHelpers[0].once('result', () => {
+      helper.derivedHelpers[0].once('result', () => {
         const hasAutomaticInsights = this.mainIndex
           .getScopedResults()
           .some(({ results }) => results?._automaticInsights);
@@ -435,8 +429,7 @@ See ${createDocumentationLink({
     // The helper needs to be reset to perform the next search from a fresh state.
     // If not reset, it would use the state stored before calling `dispose()`.
     this.removeAllListeners();
-    this.mainHelper?.removeAllListeners();
-    this.mainHelper = null;
+    this.helper?.removeAllListeners();
     this.helper = null;
 
     this.middleware.forEach(({ instance }) => {
@@ -446,12 +439,12 @@ See ${createDocumentationLink({
 
   scheduleSearch = defer(() => {
     if (this.started) {
-      this.mainHelper!.search();
+      this.helper!.search();
     }
   });
 
   scheduleRender = defer((shouldResetStatus: boolean = true) => {
-    if (!this.mainHelper?.hasPendingRequests()) {
+    if (!this.helper?.hasPendingRequests()) {
       clearTimeout(this._searchStalledTimer);
       this._searchStalledTimer = null;
 
@@ -481,7 +474,7 @@ See ${createDocumentationLink({
     uiState: TUiState | ((previousUiState: TUiState) => TUiState),
     callOnStateChange = true
   ) {
-    if (!this.mainHelper) {
+    if (!this.helper) {
       throw new Error(
         withUsage('The `start` method needs to be called before `setUiState`.')
       );
@@ -548,13 +541,13 @@ See ${createDocumentationLink({
   }
 
   refresh() {
-    if (!this.mainHelper) {
+    if (!this.helper) {
       throw new Error(
         withUsage('The `start` method needs to be called before `refresh`.')
       );
     }
 
-    this.mainHelper.clearCache().search();
+    this.helper.clearCache().search();
   }
 }
 
diff --git a/packages/instantsearch-core/src/middlewares/__tests__/createInsightsMiddleware.ts b/packages/instantsearch-core/src/middlewares/__tests__/createInsightsMiddleware.ts
index fd15e44f51..b335c21d23 100644
--- a/packages/instantsearch-core/src/middlewares/__tests__/createInsightsMiddleware.ts
+++ b/packages/instantsearch-core/src/middlewares/__tests__/createInsightsMiddleware.ts
@@ -72,8 +72,7 @@ describe('insights', () => {
     }
 
     const getUserToken = () =>
-      (instantSearchInstance.mainHelper!.state as PlainSearchParameters)
-        .userToken;
+      (instantSearchInstance.helper!.state as PlainSearchParameters).userToken;
 
     return {
       analytics,
@@ -103,11 +102,10 @@ describe('insights', () => {
     });
     instantSearchInstance.start();
 
-    const helper = instantSearchInstance.mainHelper!;
+    const helper = instantSearchInstance.helper!;
 
     const getUserToken = () =>
-      (instantSearchInstance.mainHelper!.state as PlainSearchParameters)
-        .userToken;
+      (instantSearchInstance.helper!.state as PlainSearchParameters).userToken;
 
     return {
       analytics,
@@ -452,7 +450,7 @@ describe('insights', () => {
           insightsClient,
         })
       );
-      expect(instantSearchInstance.mainHelper!.state.clickAnalytics).toBe(true);
+      expect(instantSearchInstance.helper!.state.clickAnalytics).toBe(true);
     });
 
     it('applies clickAnalytics if $$automatic: false', () => {
@@ -463,7 +461,7 @@ describe('insights', () => {
           $$automatic: false,
         })
       );
-      expect(instantSearchInstance.mainHelper!.state.clickAnalytics).toBe(true);
+      expect(instantSearchInstance.helper!.state.clickAnalytics).toBe(true);
     });
 
     it('does not apply clickAnalytics if $$automatic: true', () => {
@@ -484,9 +482,9 @@ describe('insights', () => {
       const middleware = createInsightsMiddleware({
         insightsClient,
       })({ instantSearchInstance });
-      instantSearchInstance.mainHelper!.setPage(100);
+      instantSearchInstance.helper!.setPage(100);
       middleware.subscribe();
-      expect(instantSearchInstance.mainHelper!.state.page).toBe(100);
+      expect(instantSearchInstance.helper!.state.page).toBe(100);
     });
 
     it('adds user agent', () => {
@@ -679,7 +677,7 @@ describe('insights', () => {
 
       insightsClient('setUserToken', 'abc');
       instantSearchInstance.start();
-      instantSearchInstance.mainHelper!.setPage(100);
+      instantSearchInstance.helper!.setPage(100);
 
       instantSearchInstance.use(
         createInsightsMiddleware({
@@ -687,7 +685,7 @@ describe('insights', () => {
         })
       );
 
-      expect(instantSearchInstance.mainHelper!.state.page).toBe(100);
+      expect(instantSearchInstance.helper!.state.page).toBe(100);
       expect(getUserToken()).toEqual('abc');
     });
 
@@ -711,7 +709,7 @@ describe('insights', () => {
         createTestEnvironment({ started: false });
 
       instantSearchInstance.start();
-      instantSearchInstance.mainHelper!.setPage(100);
+      instantSearchInstance.helper!.setPage(100);
 
       instantSearchInstance.use(
         createInsightsMiddleware({
@@ -723,7 +721,7 @@ describe('insights', () => {
 
       await wait(0);
 
-      expect(instantSearchInstance.mainHelper!.state.page).toEqual(100);
+      expect(instantSearchInstance.helper!.state.page).toEqual(100);
       expect(getUserToken()).toEqual('def');
     });
 
@@ -1376,7 +1374,7 @@ describe('insights', () => {
         },
       });
 
-      instantSearchInstance.mainHelper!.derivedHelpers[0].emit('result', {
+      instantSearchInstance.helper!.derivedHelpers[0].emit('result', {
         results: { queryId: '2' },
       });
 
@@ -1567,7 +1565,7 @@ describe('insights', () => {
 
     instantSearchInstance
       .helper!.setState({
-        ...instantSearchInstance.mainHelper!.state,
+        ...instantSearchInstance.helper!.state,
         query: 'test',
       })
       .search();
diff --git a/packages/instantsearch-core/src/middlewares/createInsightsMiddleware.ts b/packages/instantsearch-core/src/middlewares/createInsightsMiddleware.ts
index 1503037151..61f7ec9cc5 100644
--- a/packages/instantsearch-core/src/middlewares/createInsightsMiddleware.ts
+++ b/packages/instantsearch-core/src/middlewares/createInsightsMiddleware.ts
@@ -170,7 +170,7 @@ export function createInsightsMiddleware<
       started() {
         insightsClient('addAlgoliaAgent', 'insights-middleware');
 
-        helper = instantSearchInstance.mainHelper!;
+        helper = instantSearchInstance.helper!;
 
         const { queue: queueAtStart } = insightsClient;
 
@@ -324,7 +324,7 @@ export function createInsightsMiddleware<
 
         const viewedObjectIDs = new Set<string>();
         let lastQueryId: string | undefined;
-        instantSearchInstance.mainHelper!.derivedHelpers[0].on(
+        instantSearchInstance.helper!.derivedHelpers[0].on(
           'result',
           ({ results }) => {
             if (
@@ -416,7 +416,7 @@ function getInitialParameters(
     instantSearchInstance._initialResults?.[instantSearchInstance.indexName]
       ?.state || {};
 
-  const stateFromHelper = instantSearchInstance.mainHelper!.state;
+  const stateFromHelper = instantSearchInstance.helper!.state;
 
   return {
     userToken: stateFromInitialResults.userToken || stateFromHelper.userToken,
diff --git a/packages/instantsearch-core/src/server.ts b/packages/instantsearch-core/src/server.ts
index 6b6999e90d..0910936332 100644
--- a/packages/instantsearch-core/src/server.ts
+++ b/packages/instantsearch-core/src/server.ts
@@ -11,7 +11,7 @@ export function waitForResults(
   search: InstantSearch,
   skipRecommend: boolean = false
 ): Promise<SearchOptions[]> {
-  const helper = search.mainHelper!;
+  const helper = search.helper!;
 
   // Extract search parameters from the search client to use them
   // later during hydration.
diff --git a/packages/instantsearch-core/src/widgets/__tests__/index-widget.test.ts b/packages/instantsearch-core/src/widgets/__tests__/index-widget.test.ts
index c600238853..6647181d23 100644
--- a/packages/instantsearch-core/src/widgets/__tests__/index-widget.test.ts
+++ b/packages/instantsearch-core/src/widgets/__tests__/index-widget.test.ts
@@ -1042,12 +1042,12 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
   describe('init', () => {
     it('forwards the `search` call to the main instance', () => {
       const instance = index({ indexName: 'indexName' });
-      const mainHelper = algoliasearchHelper({} as any, '', {});
+      const helper = algoliasearchHelper({} as any, '', {});
       const instantSearchInstance = createInstantSearch({
-        mainHelper,
+        helper,
       });
 
-      const search = jest.spyOn(mainHelper, 'search').mockImplementation();
+      const search = jest.spyOn(helper, 'search').mockImplementation();
 
       instance.init(
         createIndexInitOptions({
@@ -1064,13 +1064,13 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
 
     it('forwards the `searchForFacetValues` call to the main instance', () => {
       const instance = index({ indexName: 'indexName' });
-      const mainHelper = algoliasearchHelper({} as any, '', {});
+      const helper = algoliasearchHelper({} as any, '', {});
       const instantSearchInstance = createInstantSearch({
-        mainHelper,
+        helper,
       });
 
       const searchForFacetValues = jest
-        .spyOn(mainHelper, 'searchForFacetValues')
+        .spyOn(helper, 'searchForFacetValues')
         .mockImplementation();
 
       instance.init(
@@ -1102,9 +1102,9 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
     it('uses the internal state for the queries', () => {
       const instance = index({ indexName: 'indexName' });
       const searchClient = createSearchClient();
-      const mainHelper = algoliasearchHelper(searchClient, '', {});
+      const helper = algoliasearchHelper(searchClient, '', {});
       const instantSearchInstance = createInstantSearch({
-        mainHelper,
+        helper,
       });
 
       instance.addWidgets([
@@ -1177,9 +1177,9 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
     it('uses the index set by the widget for the queries', () => {
       const instance = index({ indexName: 'indexName' });
       const searchClient = createSearchClient();
-      const mainHelper = algoliasearchHelper(searchClient, '', {});
+      const helper = algoliasearchHelper(searchClient, '', {});
       const instantSearchInstance = createInstantSearch({
-        mainHelper,
+        helper,
       });
 
       instance.addWidgets([
@@ -1215,9 +1215,9 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
       const level1 = index({ indexName: 'level1IndexName' });
       const level2 = index({ indexName: 'level2IndexName' });
       const searchClient = createSearchClient();
-      const mainHelper = algoliasearchHelper(searchClient, '', {});
+      const helper = algoliasearchHelper(searchClient, '', {});
       const instantSearchInstance = createInstantSearch({
-        mainHelper,
+        helper,
       });
 
       level0.addWidgets([
@@ -1308,9 +1308,9 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
     it('uses the internal state for the SFFV queries', () => {
       const instance = index({ indexName: 'indexName' });
       const searchClient = createSearchClient();
-      const mainHelper = algoliasearchHelper(searchClient, '', {});
+      const helper = algoliasearchHelper(searchClient, '', {});
       const instantSearchInstance = createInstantSearch({
-        mainHelper,
+        helper,
       });
 
       instance.addWidgets([
@@ -1447,9 +1447,9 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
         const level2 = index({ indexName: 'level2IndexName' });
         const level3 = index({ indexName: 'level3IndexName' });
         const searchClient = createSearchClient();
-        const mainHelper = algoliasearchHelper(searchClient, '', {});
+        const helper = algoliasearchHelper(searchClient, '', {});
         const instantSearchInstance = createInstantSearch({
-          mainHelper,
+          helper,
         });
 
         level0.addWidgets([
@@ -1658,9 +1658,9 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
         const level2 = index({ indexName: 'level2IndexName' });
         const level3 = index({ indexName: 'level3IndexName' });
         const searchClient = createSearchClient();
-        const mainHelper = algoliasearchHelper(searchClient, '', {});
+        const helper = algoliasearchHelper(searchClient, '', {});
         const instantSearchInstance = createInstantSearch({
-          mainHelper,
+          helper,
         });
 
         level0.addWidgets([
@@ -1785,9 +1785,9 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
         const level2 = index({ indexName: 'level2IndexName' });
         const level3 = index({ indexName: 'level3IndexName' });
         const searchClient = createSearchClient();
-        const mainHelper = algoliasearchHelper(searchClient, '', {});
+        const helper = algoliasearchHelper(searchClient, '', {});
         const instantSearchInstance = createInstantSearch({
-          mainHelper,
+          helper,
         });
 
         level0.addWidgets([
@@ -2269,9 +2269,9 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
       const level0 = index({ indexName: 'level0IndexName' });
 
       const searchClient = createSearchClient();
-      const mainHelper = algoliasearchHelper(searchClient, '', {});
+      const helper = algoliasearchHelper(searchClient, '', {});
       const instantSearchInstance = createInstantSearch({
-        mainHelper,
+        helper,
         _initialUiState: {
           level0IndexName: {
             query: 'something',
@@ -2441,15 +2441,15 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
     test('calls `getRenderState` with the index render state', () => {
       const searchIndex = index({ indexName: 'indexName' });
       const searchClient = createSearchClient();
-      const mainHelper = algoliasearchHelper(searchClient, 'indexName', {});
-      const instantSearchInstance = createInstantSearch({ mainHelper });
+      const helper = algoliasearchHelper(searchClient, 'indexName', {});
+      const instantSearchInstance = createInstantSearch({ helper });
       const searchBox = createSearchBox({
         dependsOn: 'search',
-        getRenderState: jest.fn((renderState, { helper }) => {
+        getRenderState: jest.fn((renderState, { helper: { state } }) => {
           return {
             ...renderState,
             searchBox: {
-              query: helper.state.query || '',
+              query: state.query || '',
               refine: () => {},
               clear: () => {},
               widgetParams: {},
@@ -2554,19 +2554,19 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
       it('derives only once', () => {
         const instance = index({ indexName: 'test' });
 
-        const mainHelper = algoliasearchHelper(createSearchClient(), '');
+        const helper = algoliasearchHelper(createSearchClient(), '');
 
-        const instantSearchInstance = createInstantSearch({ mainHelper });
+        const instantSearchInstance = createInstantSearch({ helper });
 
         expect(instance.getHelper()).toBe(null);
 
         instance.init(createIndexInitOptions({ instantSearchInstance }));
 
-        expect(mainHelper.derivedHelpers.length).toBe(1);
+        expect(helper.derivedHelpers.length).toBe(1);
 
         instance.init(createIndexInitOptions({ instantSearchInstance }));
 
-        expect(mainHelper.derivedHelpers.length).toBe(1);
+        expect(helper.derivedHelpers.length).toBe(1);
       });
     });
   });
@@ -2892,9 +2892,9 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
           })
         ),
       });
-      const mainHelper = algoliasearchHelper(searchClient, '', {});
+      const helper = algoliasearchHelper(searchClient, '', {});
       const instantSearchInstance = createInstantSearch({
-        mainHelper,
+        helper,
       });
 
       const fbt = createFrequentlyBoughtTogether({
@@ -2910,9 +2910,9 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
           parent: null,
         })
       );
-      mainHelper.search();
+      helper.search();
       await wait(0);
-      mainHelper.recommend();
+      helper.recommend();
       await wait(0);
 
       instance.render({
@@ -3066,9 +3066,9 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
     it('removes the DerivedHelper', () => {
       const instance = index({ indexName: 'indexName' });
       const searchClient = createSearchClient();
-      const mainHelper = algoliasearchHelper(searchClient, '', {});
+      const helper = algoliasearchHelper(searchClient, '', {});
       const instantSearchInstance = createInstantSearch({
-        mainHelper,
+        helper,
       });
 
       instance.init(
@@ -3078,11 +3078,11 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/index-widge
         })
       );
 
-      expect(mainHelper.derivedHelpers).toHaveLength(1);
+      expect(helper.derivedHelpers).toHaveLength(1);
 
       instance.dispose(createDisposeOptions());
 
-      expect(mainHelper.derivedHelpers).toHaveLength(0);
+      expect(helper.derivedHelpers).toHaveLength(0);
     });
 
     it('does not crash when calling `dispose` before `init`', () => {
diff --git a/packages/instantsearch-core/src/widgets/index-widget.ts b/packages/instantsearch-core/src/widgets/index-widget.ts
index 719a12c620..b9bba96d73 100644
--- a/packages/instantsearch-core/src/widgets/index-widget.ts
+++ b/packages/instantsearch-core/src/widgets/index-widget.ts
@@ -485,10 +485,10 @@ export const index = (widgetParams: IndexWidgetParams): IndexWidget => {
       localParent = parent;
       localUiState = uiState[indexId] || {};
 
-      // The `mainHelper` is already defined at this point. The instance is created
+      // The helper is already defined at this point. The instance is created
       // inside InstantSearch at the `start` method, which occurs before the `init`
       // step.
-      const mainHelper = instantSearchInstance.mainHelper!;
+      const searchHelper = instantSearchInstance.helper!;
       const parameters = getLocalWidgetsSearchParameters(localWidgets, {
         uiState: localUiState,
         initialSearchParameters: new algoliasearchHelper.SearchParameters({
@@ -527,14 +527,14 @@ export const index = (widgetParams: IndexWidgetParams): IndexWidget => {
 
           // We don't trigger a search when controlled because it becomes the
           // responsibility of `setUiState`.
-          return mainHelper;
+          return searchHelper;
         }
 
-        return mainHelper.search();
+        return searchHelper.search();
       };
 
       helper.searchWithoutTriggeringOnStateChange = () => {
-        return mainHelper.search();
+        return searchHelper.search();
       };
 
       // We use the same pattern for the `searchForFacetValues`.
@@ -546,7 +546,7 @@ export const index = (widgetParams: IndexWidgetParams): IndexWidget => {
       ) => {
         const state = helper!.state.setQueryParameters(userState);
 
-        return mainHelper.searchForFacetValues(
+        return searchHelper.searchForFacetValues(
           facetName,
           facetValue,
           maxFacetHits,
@@ -554,10 +554,10 @@ export const index = (widgetParams: IndexWidgetParams): IndexWidget => {
         );
       };
 
-      derivedHelper = mainHelper.derive(
+      derivedHelper = searchHelper.derive(
         () =>
           mergeSearchParameters(
-            mainHelper.state,
+            searchHelper.state,
             ...resolveSearchParameters(this)
           ),
         () => this.getHelper()!.recommendState
@@ -710,7 +710,7 @@ export const index = (widgetParams: IndexWidgetParams): IndexWidget => {
       // then would no longer be thrown for global handlers.
       if (
         instantSearchInstance.status === 'error' &&
-        !instantSearchInstance.mainHelper!.hasPendingRequests() &&
+        !instantSearchInstance.helper!.hasPendingRequests() &&
         lastValidSearchParameters
       ) {
         helper!.setState(lastValidSearchParameters);
diff --git a/packages/instantsearch-core/test/createInstantSearch.ts b/packages/instantsearch-core/test/createInstantSearch.ts
index 09ef3a1bab..db2d63d115 100644
--- a/packages/instantsearch-core/test/createInstantSearch.ts
+++ b/packages/instantsearch-core/test/createInstantSearch.ts
@@ -9,13 +9,13 @@ export const createInstantSearch = (
   args: Partial<InstantSearch> = {}
 ): InstantSearch => {
   const { indexName = 'indexName', client = createSearchClient() } = args;
-  const mainHelper = algoliasearchHelper(client, indexName, {});
+  const helper = algoliasearchHelper(client, indexName, {});
   const mainIndex = index({ indexName });
 
   return {
     indexName,
     mainIndex,
-    mainHelper,
+    helper,
     client,
     started: false,
     status: 'idle',
@@ -27,7 +27,6 @@ export const createInstantSearch = (
       this.started = false;
     },
     refresh: jest.fn(),
-    helper: mainHelper, // @TODO: use the Helper from the index once the RoutingManger uses the index
     middleware: [],
     renderState: {},
     scheduleStalledRender: defer(jest.fn()),
diff --git a/packages/instantsearch-core/test/createWidget.ts b/packages/instantsearch-core/test/createWidget.ts
index 7f9b57c267..a35b361aab 100644
--- a/packages/instantsearch-core/test/createWidget.ts
+++ b/packages/instantsearch-core/test/createWidget.ts
@@ -55,7 +55,7 @@ export const createRenderOptions = (
   const response = createMultiSearchResponse();
   const helper = args.helper || instantSearchInstance.helper!;
   const results = new algoliasearchHelper.SearchResults(
-    instantSearchInstance.helper!.state,
+    helper.state,
     response.results as Array<SearchResponse<any>>
   );
 
diff --git a/packages/instantsearch.js/src/widgets/dynamic-widgets/__tests__/dynamic-widgets-test.ts b/packages/instantsearch.js/src/widgets/dynamic-widgets/__tests__/dynamic-widgets-test.ts
index 3600a5f4e7..9867eb1890 100644
--- a/packages/instantsearch.js/src/widgets/dynamic-widgets/__tests__/dynamic-widgets-test.ts
+++ b/packages/instantsearch.js/src/widgets/dynamic-widgets/__tests__/dynamic-widgets-test.ts
@@ -185,7 +185,7 @@ describe('dynamicWidgets()', () => {
       indexWidget.init(createInitOptions({ instantSearchInstance }));
 
       // set results to the relevant index, so it renders all children
-      instantSearchInstance.mainHelper!.derivedHelpers[0].lastResults =
+      instantSearchInstance.helper!.derivedHelpers[0].lastResults =
         new SearchResults(
           indexWidget.getWidgetSearchParameters(new SearchParameters(), {
             uiState: {},
@@ -450,7 +450,7 @@ describe('dynamicWidgets()', () => {
       indexWidget.init(createInitOptions({ instantSearchInstance }));
 
       // set results to the relevant index, so it renders all children
-      instantSearchInstance.mainHelper!.derivedHelpers[0].lastResults =
+      instantSearchInstance.helper!.derivedHelpers[0].lastResults =
         new SearchResults(
           indexWidget.getWidgetSearchParameters(new SearchParameters(), {
             uiState: {},
diff --git a/packages/instantsearch.js/src/widgets/hits/__tests__/hits.test.tsx b/packages/instantsearch.js/src/widgets/hits/__tests__/hits.test.tsx
index 391bfafc35..59a62c265b 100644
--- a/packages/instantsearch.js/src/widgets/hits/__tests__/hits.test.tsx
+++ b/packages/instantsearch.js/src/widgets/hits/__tests__/hits.test.tsx
@@ -203,7 +203,6 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/hits/js/"
 
       search.start();
       // prevent warning from insights view event because insightsClient isn't yet loaded
-      // @ts-ignore
       search.helper!.state.userToken = 'userToken';
 
       await wait(0);
diff --git a/packages/instantsearch.js/src/widgets/infinite-hits/__tests__/infinite-hits.test.tsx b/packages/instantsearch.js/src/widgets/infinite-hits/__tests__/infinite-hits.test.tsx
index 22829b8ccb..b0d0a5d44b 100644
--- a/packages/instantsearch.js/src/widgets/infinite-hits/__tests__/infinite-hits.test.tsx
+++ b/packages/instantsearch.js/src/widgets/infinite-hits/__tests__/infinite-hits.test.tsx
@@ -190,7 +190,6 @@ describe('infiniteHits', () => {
 
       search.start();
       // prevent warning from insights view event because insightsClient isn't yet loaded
-      // @ts-ignore
       search.helper!.state.userToken = 'userToken';
 
       await wait(0);
diff --git a/packages/instantsearch.js/src/widgets/menu-select/__tests__/menu-select-test.ts b/packages/instantsearch.js/src/widgets/menu-select/__tests__/menu-select-test.ts
index 56552c8c8f..9d9769126c 100644
--- a/packages/instantsearch.js/src/widgets/menu-select/__tests__/menu-select-test.ts
+++ b/packages/instantsearch.js/src/widgets/menu-select/__tests__/menu-select-test.ts
@@ -215,7 +215,7 @@ describe('menuSelect', () => {
 
       await wait(0);
 
-      expect(search.helper!.state).toEqual(
+      expect(search.mainIndex.getHelper()!.state).toEqual(
         new SearchParameters({
           index: 'test',
           hierarchicalFacets: [{ attributes: ['test'], name: 'test' }],
diff --git a/packages/react-instantsearch-core/src/lib/useInstantSearchApi.ts b/packages/react-instantsearch-core/src/lib/useInstantSearchApi.ts
index 45c45d47d6..883961a6ea 100644
--- a/packages/react-instantsearch-core/src/lib/useInstantSearchApi.ts
+++ b/packages/react-instantsearch-core/src/lib/useInstantSearchApi.ts
@@ -140,7 +140,10 @@ export function useInstantSearchApi<TUiState extends UiState, TRouteState>(
     const prevProps = prevPropsRef.current;
 
     if (prevProps.indexName !== props.indexName) {
-      search.helper!.setIndex(props.indexName || '').search();
+      search.mainIndex
+        .getHelper()!
+        .setIndex(props.indexName || '')
+        .search();
       prevPropsRef.current = props;
     }
 
@@ -154,7 +157,7 @@ export function useInstantSearchApi<TUiState extends UiState, TRouteState>(
         ...defaultUserAgents,
         serverContext && serverUserAgent,
       ]);
-      search.mainHelper!.setClient(props.searchClient).search();
+      search.helper!.setClient(props.searchClient).search();
       prevPropsRef.current = props;
     }
 
diff --git a/packages/react-instantsearch-nextjs/src/InitializePromise.tsx b/packages/react-instantsearch-nextjs/src/InitializePromise.tsx
index 9b658c868e..505f882762 100644
--- a/packages/react-instantsearch-nextjs/src/InitializePromise.tsx
+++ b/packages/react-instantsearch-nextjs/src/InitializePromise.tsx
@@ -63,8 +63,8 @@ export function InitializePromise({ nonce }: InitializePromiseProps) {
   // Extract search parameters from the search client to use them
   // later during hydration.
   let requestParamsList: SearchOptions[];
-  search.mainHelper!.setClient({
-    ...search.mainHelper!.getClient(),
+  search.helper!.setClient({
+    ...search.helper!.getClient(),
     search(queries) {
       requestParamsList = queries.map(({ params }) => params);
       return search.client.search(queries);
@@ -77,13 +77,13 @@ export function InitializePromise({ nonce }: InitializePromiseProps) {
     new Promise<void>((resolve) => {
       let searchReceived = false;
       let recommendReceived = false;
-      search.mainHelper!.derivedHelpers[0].once('result', () => {
+      search.helper!.derivedHelpers[0].once('result', () => {
         searchReceived = true;
         if (!search._hasRecommendWidget || recommendReceived) {
           resolve();
         }
       });
-      search.mainHelper!.derivedHelpers[0].once('recommend:result', () => {
+      search.helper!.derivedHelpers[0].once('recommend:result', () => {
         recommendReceived = true;
         if (!search._hasSearchWidget || searchReceived) {
           resolve();
diff --git a/packages/react-instantsearch-nextjs/src/TriggerSearch.ts b/packages/react-instantsearch-nextjs/src/TriggerSearch.ts
index 7a2fdcb9c7..d4e3ed042c 100644
--- a/packages/react-instantsearch-nextjs/src/TriggerSearch.ts
+++ b/packages/react-instantsearch-nextjs/src/TriggerSearch.ts
@@ -9,8 +9,8 @@ export function TriggerSearch() {
 
   if (waitForResultsRef?.current?.status === 'pending') {
     instantsearch._hasSearchWidget &&
-      instantsearch.mainHelper?.searchOnlyWithDerivedHelpers();
-    instantsearch._hasRecommendWidget && instantsearch.mainHelper?.recommend();
+      instantsearch.helper?.searchOnlyWithDerivedHelpers();
+    instantsearch._hasRecommendWidget && instantsearch.helper?.recommend();
   }
 
   return null;
diff --git a/packages/vue-instantsearch/src/components/Stats.vue b/packages/vue-instantsearch/src/components/Stats.vue
index e65ce20761..22eb20291f 100644
--- a/packages/vue-instantsearch/src/components/Stats.vue
+++ b/packages/vue-instantsearch/src/components/Stats.vue
@@ -1,9 +1,6 @@
 <template>
   <div v-if="state" :class="suit()">
-    <slot
-      v-bind="state"
-      :results="state.instantSearchInstance.helper.lastResults"
-    >
+    <slot v-bind="state">
       <!-- prettier-ignore -->
       <span :class="suit('text')"
         ><template v-if="state.areHitsSorted"
diff --git a/packages/vue-instantsearch/src/util/__tests__/createServerRootMixin.test.js b/packages/vue-instantsearch/src/util/__tests__/createServerRootMixin.test.js
index 2e95a9616a..be746b2fa0 100644
--- a/packages/vue-instantsearch/src/util/__tests__/createServerRootMixin.test.js
+++ b/packages/vue-instantsearch/src/util/__tests__/createServerRootMixin.test.js
@@ -1026,7 +1026,7 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/instantsear
       expect(instantsearch.mainIndex.getHelper()).not.toBeNull();
     });
 
-    it('sets helper & mainHelper', () => {
+    it('sets helper', () => {
       const serialized = createSerializedState();
 
       const app = {
@@ -1053,14 +1053,12 @@ See documentation: https://www.algolia.com/doc/api-reference/widgets/instantsear
       } = mount(app);
 
       expect(instantsearch.helper).toBe(null);
-      expect(instantsearch.mainHelper).toBe(null);
 
       instantsearch.hydrate({
         hello: serialized,
       });
 
       expect(instantsearch.helper).toEqual(expect.any(AlgoliaSearchHelper));
-      expect(instantsearch.mainHelper).toEqual(expect.any(AlgoliaSearchHelper));
     });
   });
 
diff --git a/packages/vue-instantsearch/src/util/createInstantSearchComponent.js b/packages/vue-instantsearch/src/util/createInstantSearchComponent.js
index b19e41dc71..61ac2daad8 100644
--- a/packages/vue-instantsearch/src/util/createInstantSearchComponent.js
+++ b/packages/vue-instantsearch/src/util/createInstantSearchComponent.js
@@ -21,17 +21,17 @@ export const createInstantSearchComponent = (component) => ({
       );
 
       this.instantSearchInstance.client = searchClient;
-      if (this.instantSearchInstance.mainHelper) {
-        this.instantSearchInstance.mainHelper.setClient(searchClient).search();
+      if (this.instantSearchInstance.helper) {
+        this.instantSearchInstance.helper.setClient(searchClient).search();
       }
     },
     indexName(indexName) {
       if (
-        this.instantSearchInstance.helper &&
-        this.instantSearchInstance.mainHelper
+        this.instantSearchInstance.mainIndex &&
+        this.instantSearchInstance.mainIndex.getHelper()
       ) {
-        this.instantSearchInstance.helper.setIndex(indexName || '');
-        this.instantSearchInstance.mainHelper
+        this.instantSearchInstance.mainIndex
+          .getHelper()
           .setIndex(indexName || '')
           .search();
       }