diff --git a/apps/backend/lambdas/users/handler.ts b/apps/backend/lambdas/users/handler.ts
index 582ea72..4bcedff 100644
--- a/apps/backend/lambdas/users/handler.ts
+++ b/apps/backend/lambdas/users/handler.ts
@@ -115,7 +115,54 @@ export const handler = async (event: any): Promise<APIGatewayProxyResult> => {
       return json(200, { ok: true, route: 'PATCH /users/{userId}', pathParams: { userId }, body: { email: updatedUser!.email, name: updatedUser!.name, isAdmin: updatedUser!.is_admin } });
     }
 
-    // <<< ROUTES-END 
+    // POST /users
+    if ((normalizedPath === '/users' || normalizedPath === '') && method === 'POST') {
+      const body = event.body
+        ? (JSON.parse(event.body) as Record<string, unknown>)
+        : {};
+
+      // extract fields to create user
+      let email = body.email as string;
+      let name = body.name as string;
+      let isAdmin = body.isAdmin as boolean;
+      if (!email || !name || typeof isAdmin !== 'boolean') {
+        return json(400, { message: 'email, name, and isAdmin are required' });
+      }
+
+      // Check if user with this email already exists
+      const existingUser = await db
+        .selectFrom('branch.users')
+        .where('email', '=', email)
+        .selectAll()
+        .executeTakeFirst();
+
+      if (existingUser) {
+        return json(409, { message: 'User with this email already exists' });
+      }
+        
+      // insert new user (user_id auto-increments)
+      try {
+        await db
+          .insertInto('branch.users')
+          .values({ email, name, is_admin: isAdmin })
+          .execute();
+      } catch (err) {
+        console.error('Database insert error:', err);
+        return json(500, { message: 'Failed to create user' });
+      }
+
+      return json(201, {
+        ok: true,
+        route: 'POST /users',
+        pathParams: {},
+        body: {
+          email,
+          name,
+          isAdmin,
+        },
+      });
+    }
+    // <<< ROUTES-END
 
     return json(404, { message: 'Not Found', path: normalizedPath, method });
   } catch (err) {
diff --git a/apps/backend/lambdas/users/openapi.yaml b/apps/backend/lambdas/users/openapi.yaml
index 961f810..c639172 100644
--- a/apps/backend/lambdas/users/openapi.yaml
+++ b/apps/backend/lambdas/users/openapi.yaml
@@ -34,6 +34,28 @@ paths:
       responses:
         '200':
           description: OK
+    post:
+      summary: POST /users
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              type: object
+              properties:
+                name:
+                  type: string
+                email:
+                  type: string
+                isAdmin:
+                  type: boolean
+      responses:
+        '201':
+          description: Success
+        '400':
+          description: Bad Request
+        '500':
+          description: Internal Server Error
   /{userId}:
     patch:
       summary: PATCH /{userId}
diff --git a/apps/backend/lambdas/users/test/user.unit.test.ts b/apps/backend/lambdas/users/test/user.unit.test.ts
new file mode 100644
index 0000000..dad172d
--- /dev/null
+++ b/apps/backend/lambdas/users/test/user.unit.test.ts
@@ -0,0 +1,185 @@
+import { describe, test, expect, beforeEach, jest } from '@jest/globals';
+
+// Mock the database module BEFORE importing handler
+jest.mock('../db');
+
+import { handler } from '../handler';
+import db from '../db';
+
+const mockDb = db as any;
+
+// Helper function to create a POST event
+function postEvent(body: Record<string, unknown>) {
+  return {
+    rawPath: '/users',
+    requestContext: {
+      http: {
+        method: 'POST',
+      },
+    },
+    body: JSON.stringify(body),
+  };
+}
+
+describe('POST /users unit tests', () => {
+  beforeEach(() => {
+    jest.clearAllMocks();
+  });
+
+  describe('Input Validation', () => {
+    test('400: missing email field', async () => {
+      const res = await handler(
+        postEvent({
+          name: 'John Doe',
+          isAdmin: false,
+        })
+      );
+
+      expect(res.statusCode).toBe(400);
+      const json = JSON.parse(res.body);
+      expect(json.message).toBeDefined();
+      expect(json.message).toContain('required');
+    });
+
+    test('400: missing name field', async () => {
+      const res = await handler(
+        postEvent({
+          email: 'john@example.com',
+          isAdmin: false,
+        })
+      );
+
+      expect(res.statusCode).toBe(400);
+      const json = JSON.parse(res.body);
+      expect(json.message).toBeDefined();
+      expect(json.message).toContain('required');
+    });
+
+    test('400: missing isAdmin field', async () => {
+      const res = await handler(
+        postEvent({
+          name: 'John Doe',
+          email: 'john@example.com',
+        })
+      );
+
+      expect(res.statusCode).toBe(400);
+      const json = JSON.parse(res.body);
+      expect(json.message).toBeDefined();
+      expect(json.message).toContain('required');
+    });
+
+    test('400: isAdmin is not a boolean', async () => {
+      const res = await handler(
+        postEvent({
+          name: 'John Doe',
+          email: 'john@example.com',
+          isAdmin: 'yes',
+        })
+      );
+
+      expect(res.statusCode).toBe(400);
+      const json = JSON.parse(res.body);
+      expect(json.message).toBeDefined();
+      expect(json.message).toContain('required');
+    });
+
+    test('400: empty email field', async () => {
+      const res = await handler(
+        postEvent({
+          name: 'John Doe',
+          email: '',
+          isAdmin: false,
+        })
+      );
+
+      expect(res.statusCode).toBe(400);
+      const json = JSON.parse(res.body);
+      expect(json.message).toContain('required');
+    });
+
+    test('400: empty name field', async () => {
+      const res = await handler(
+        postEvent({
+          name: '',
+          email: 'john@example.com',
+          isAdmin: false,
+        })
+      );
+
+      expect(res.statusCode).toBe(400);
+      const json = JSON.parse(res.body);
+      expect(json.message).toContain('required');
+    });
+  });
+
+  describe('Response Format', () => {
+  });
+
+  describe('Success Cases', () => {
+    test('201: successful POST returns 201 status and correct response shape', async () => {
+      // Setup mocks for successful user creation
+      // Mock the email check to return null (user doesn't exist)
+      const whereChain = {
+        selectAll: jest.fn().mockReturnValue({
+          executeTakeFirst: (jest.fn() as any).mockResolvedValue(null),
+        }),
+      };
+      mockDb.selectFrom.mockReturnValue({
+        where: jest.fn().mockReturnValue(whereChain),
+      });
+
+      // Mock the insert
+      mockDb.insertInto.mockReturnValue({
+        values: jest.fn().mockReturnValue({
+          execute: (jest.fn() as any).mockResolvedValue(undefined),
+        }),
+      });
+
+      const res = await handler(
+        postEvent({
+          name: 'John Doe',
+          email: 'john@example.com',
+          isAdmin: false,
+        })
+      );
+
+      expect(res.statusCode).toBe(201);
+      const json = JSON.parse(res.body);
+      expect(json).toHaveProperty('ok');
+      expect(json).toHaveProperty('route');
+      expect(json).toHaveProperty('pathParams');
+      expect(json).toHaveProperty('body');
+    });
+
+    test('409: returns 409 when user already exists', async () => {
+      // Mock: user already exists
+      const whereChain = {
+        selectAll: jest.fn().mockReturnValue({
+          executeTakeFirst: (jest.fn() as any).mockResolvedValue({
+            user_id: 1,
+            name: 'Existing User',
+            email: 'existing@example.com',
+            is_admin: false,
+            created_at: new Date(),
+          }),
+        }),
+      };
+      mockDb.selectFrom.mockReturnValue({
+        where: jest.fn().mockReturnValue(whereChain),
+      });
+
+      const res = await handler(
+        postEvent({
+          name: 'New User',
+          email: 'existing@example.com',
+          isAdmin: true,
+        })
+      );
+
+      expect(res.statusCode).toBe(409);
+      const json = JSON.parse(res.body);
+      expect(json).toHaveProperty('message');
+    });
+  });
+});
diff --git a/apps/backend/lambdas/users/test/users.test.ts b/apps/backend/lambdas/users/test/users.test.ts
index 0257301..2d9b897 100644
--- a/apps/backend/lambdas/users/test/users.test.ts
+++ b/apps/backend/lambdas/users/test/users.test.ts
@@ -167,3 +167,47 @@ test("get users error", async () => {
   let res = await fetch("http://localhost:3000/user")
   expect(res.status).toBe(404);
 });
+
+test("POST user success case", async () => {
+  let res = await fetch("http://localhost:3000/users", {
+    method: "POST",
+    body: JSON.stringify({
+      name: "Jane Branch",
+      email: "jane@branch.com",
+      isAdmin: true
+    })
+  });
+
+  expect(res.status).toBe(201);
+
+  let body = await res.json();
+
+  expect(body.ok).toBe(true);
+  expect(body.body.name).toBe("Jane Branch");
+  expect(body.body.email).toBe("jane@branch.com");
+  expect(body.body.isAdmin).toBe(true);
+});
+
+test("POST user 400 case when invalid email is sent", async () => {
+  let res = await fetch("http://localhost:3000/users", {
+    method: "POST",
+    body: JSON.stringify({
+      name: "Invalid User",
+      email: "",
+      isAdmin: false
+    })
+  });
+
+  expect(res.status).toBe(400);
+});
+
+test("POST user 400 case when request sent with missing fields", async () => {
+  let res = await fetch("http://localhost:3000/users", {
+    method: "POST",
+    body: JSON.stringify({
+      name: "Invalid User",
+    }) // missing email and admin fields
+  });
+
+  expect(res.status).toBe(400);
+});
\ No newline at end of file