diff --git a/packages/js/README.md b/packages/js/README.md
index c4a4f8a..effeb27 100644
--- a/packages/js/README.md
+++ b/packages/js/README.md
@@ -25,12 +25,14 @@ import formbricks from "@formbricks/js";
 
 if (typeof window !== "undefined") {
   formbricks.setup({
-    environmentId: "your-environment-id",
+    workspaceId: "your-workspace-id",
     appUrl: "https://app.formbricks.com",
   });
 }
 ```
 
-Replace your-environment-id with your actual environment ID. You can find your environment ID in the **Setup Checklist** in the Formbricks settings. If you want to use the user identification feature, please check out [our docs for details](https://formbricks.com/docs/app-surveys/user-identification).
+Replace your-workspace-id with your actual workspace ID. You can find your workspace ID in the **Setup Checklist** in the Formbricks settings. If you want to use the user identification feature, please check out [our docs for details](https://formbricks.com/docs/app-surveys/user-identification).
+
+> `environmentId` is still accepted for backward compatibility but is deprecated and will be removed in a future version. Prefer `workspaceId`.
 
 For more detailed guides for different frameworks, check out our [Framework Guides](https://formbricks.com/docs/getting-started/framework-guides).
diff --git a/packages/js/src/index.test.ts b/packages/js/src/index.test.ts
index 01cdeb6..15e01db 100644
--- a/packages/js/src/index.test.ts
+++ b/packages/js/src/index.test.ts
@@ -24,7 +24,18 @@ describe("formbricks", () => {
     expect(typeof formbricks).toBe("object");
   });
 
-  test("should delegate setup to setup()", async () => {
+  test("should delegate setup to setup() (workspaceId)", async () => {
+    const setupArgs = {
+      workspaceId: "ws123",
+      appUrl: "https://app.formbricks.com",
+    };
+
+    await formbricks.setup(setupArgs);
+
+    expect(mockSetup).toHaveBeenCalledWith(setupArgs);
+  });
+
+  test("should delegate setup to setup() (environmentId backward compat)", async () => {
     const setupArgs = {
       environmentId: "env123",
       appUrl: "https://app.formbricks.com",
@@ -212,6 +223,7 @@ describe("type safety", () => {
 
   test("should maintain type safety for known methods", () => {
     const testTypeSafety = () => {
+      void formbricks.setup({ workspaceId: "ws", appUrl: "url" });
       void formbricks.setup({ environmentId: "env", appUrl: "url" });
       void formbricks.track("event");
       void formbricks.setEmail("email");
diff --git a/packages/js/src/lib/load-formbricks.test.ts b/packages/js/src/lib/load-formbricks.test.ts
index 3565c75..6b72aa4 100644
--- a/packages/js/src/lib/load-formbricks.test.ts
+++ b/packages/js/src/lib/load-formbricks.test.ts
@@ -1,7 +1,8 @@
 import { afterEach, beforeEach, describe, expect, test, vi } from "vitest";
+import type { TSetupConfig } from "../types/formbricks";
 
 // We need to import the module after each reset
-let setup: (config: { appUrl: string; environmentId: string }) => Promise<void>;
+let setup: (config: TSetupConfig) => Promise<void>;
 let callMethod: (method: string, ...args: unknown[]) => Promise<void>;
 
 // Mock the globalThis formbricks object
@@ -191,7 +192,7 @@ describe("load-formbricks", () => {
         );
       });
 
-      test("should log error when environmentId is missing", async () => {
+      test("should log error when both workspaceId and environmentId are missing", async () => {
         const consoleSpy = createConsoleErrorSpy();
 
         await setup({
@@ -200,10 +201,83 @@ describe("load-formbricks", () => {
         });
 
         expect(consoleSpy).toHaveBeenCalledWith(
-          "🧱 Formbricks - Error: environmentId is required",
+          "🧱 Formbricks - Error: workspaceId or environmentId is required",
         );
       });
 
+      test("should handle setup call with workspaceId", async () => {
+        const setupArgs = {
+          appUrl: "https://app.formbricks.com",
+          workspaceId: "ws123",
+        };
+
+        const mockAppendChild = vi
+          .spyOn(document.head, "appendChild")
+          .mockImplementation(createSuccessfulScriptMock());
+
+        await setup(setupArgs);
+
+        expect(mockAppendChild).toHaveBeenCalledWith(
+          expect.objectContaining({
+            src: `${setupArgs.appUrl}/js/formbricks.umd.cjs`,
+            type: "text/javascript",
+            async: true,
+          }),
+        );
+        expect(mockFormbricks.setup).toHaveBeenCalledWith(setupArgs);
+      });
+
+      test("should warn about deprecation when only environmentId is provided", async () => {
+        const consoleWarnSpy = createConsoleWarnSpy();
+
+        vi.spyOn(document.head, "appendChild").mockImplementation(
+          createSuccessfulScriptMock(),
+        );
+
+        await setup({
+          appUrl: "https://app.formbricks.com",
+          environmentId: "env123",
+        });
+
+        expect(consoleWarnSpy).toHaveBeenCalledWith(
+          "🧱 Formbricks - Warning: environmentId is deprecated and will be removed in a future version. Please use workspaceId instead.",
+        );
+      });
+
+      test("should not warn about deprecation when workspaceId is provided", async () => {
+        const consoleWarnSpy = createConsoleWarnSpy();
+
+        vi.spyOn(document.head, "appendChild").mockImplementation(
+          createSuccessfulScriptMock(),
+        );
+
+        await setup({
+          appUrl: "https://app.formbricks.com",
+          workspaceId: "ws123",
+          environmentId: "env123",
+        });
+
+        expect(consoleWarnSpy).not.toHaveBeenCalledWith(
+          expect.stringContaining("environmentId is deprecated"),
+        );
+      });
+
+      test("should pass both workspaceId and environmentId through when both provided", async () => {
+        const setupArgs = {
+          appUrl: "https://app.formbricks.com",
+          workspaceId: "ws123",
+          environmentId: "env123",
+        };
+
+        vi.spyOn(document.head, "appendChild").mockImplementation(
+          createSuccessfulScriptMock(),
+        );
+
+        await setup(setupArgs);
+
+        expect(mockFormbricks.setup).toHaveBeenCalledWith(setupArgs);
+      });
+
       test("should not load script again if formbricks is already available", async () => {
         const setupArgs = {
           appUrl: "https://app.formbricks.com",
diff --git a/packages/js/src/lib/load-formbricks.ts b/packages/js/src/lib/load-formbricks.ts
index b18e410..9ae5b4f 100644
--- a/packages/js/src/lib/load-formbricks.ts
+++ b/packages/js/src/lib/load-formbricks.ts
@@ -1,4 +1,4 @@
-import type { TFormbricks } from "../types/formbricks";
+import type { TFormbricks, TSetupConfig } from "../types/formbricks";
 
 type Result<T, E = Error> = { ok: true; data: T } | { ok: false; error: E };
 
@@ -76,30 +76,37 @@ const loadFormbricksSDK = async (appUrl: string): Promise<Result<void>> => {
   return loadPromise;
 };
 
-const validateSetupArgs = (
-  config: unknown,
-): { appUrl: string; environmentId: string } | null => {
-  const { appUrl, environmentId } = config as {
-    appUrl: string;
-    environmentId: string;
-  };
+const validateSetupArgs = (config: TSetupConfig): TSetupConfig | null => {
+  const { appUrl, environmentId, workspaceId } = config;
 
   if (!appUrl) {
     console.error("🧱 Formbricks - Error: appUrl is required");
     return null;
   }
 
-  if (!environmentId) {
-    console.error("🧱 Formbricks - Error: environmentId is required");
+  if (!workspaceId && !environmentId) {
+    console.error(
+      "🧱 Formbricks - Error: workspaceId or environmentId is required",
+    );
     return null;
   }
 
+  if (environmentId && !workspaceId) {
+    console.warn(
+      "🧱 Formbricks - Warning: environmentId is deprecated and will be removed in a future version. Please use workspaceId instead.",
+    );
+  }
+
   // Removing trailing slash
   const appUrlWithoutTrailingSlash = appUrl.endsWith("/")
     ? appUrl.slice(0, -1)
     : appUrl;
 
-  return { appUrl: appUrlWithoutTrailingSlash, environmentId };
+  return {
+    appUrl: appUrlWithoutTrailingSlash,
+    ...(workspaceId ? { workspaceId } : {}),
+    ...(environmentId ? { environmentId } : {}),
+  };
 };
 
 const processQueue = (): void => {
@@ -126,10 +133,7 @@ const processQueue = (): void => {
   }
 };
 
-export const setup = async (config: {
-  appUrl: string;
-  environmentId: string;
-}): Promise<void> => {
+export const setup = async (config: TSetupConfig): Promise<void> => {
   if (isInitializing) {
     console.warn(
       "🧱 Formbricks - Warning: Formbricks is already initializing.",
diff --git a/packages/js/src/types/formbricks.ts b/packages/js/src/types/formbricks.ts
index cc3f0ad..bede833 100644
--- a/packages/js/src/types/formbricks.ts
+++ b/packages/js/src/types/formbricks.ts
@@ -3,10 +3,7 @@ export interface TFormbricks {
    * @description Initializes the Formbricks SDK.
    * @param setupConfig - The configuration for the Formbricks SDK.
    */
-  setup: (setupConfig: {
-    environmentId: string;
-    appUrl: string;
-  }) => Promise<void>;
+  setup: (setupConfig: TSetupConfig) => Promise<void>;
 
   /**
    * @description Sets the email of the user.
@@ -67,3 +64,12 @@ export interface TFormbricks {
    */
   registerRouteChange: () => Promise<void>;
 }
+
+export type TSetupConfig = {
+  workspaceId?: string;
+  /**
+   * @deprecated use workspaceId instead, environmentId will be removed in a future version
+   */
+  environmentId?: string;
+  appUrl: string;
+};