diff --git a/packages/twenty-server/src/engine/core-modules/auth/auth.module.ts b/packages/twenty-server/src/engine/core-modules/auth/auth.module.ts
index 8c973c229..f2eb77f6e 100644
--- a/packages/twenty-server/src/engine/core-modules/auth/auth.module.ts
+++ b/packages/twenty-server/src/engine/core-modules/auth/auth.module.ts
@@ -18,7 +18,7 @@ import { VerifyAuthController } from 'src/engine/core-modules/auth/controllers/v
 import { TokenService } from 'src/engine/core-modules/auth/services/token.service';
 import { GoogleAPIsService } from 'src/engine/core-modules/auth/services/google-apis.service';
 import { UserWorkspaceModule } from 'src/engine/core-modules/user-workspace/user-workspace.module';
-import { SignUpService } from 'src/engine/core-modules/auth/services/sign-up.service';
+import { SignInUpService } from 'src/engine/core-modules/auth/services/sign-in-up.service';
 import { FeatureFlagEntity } from 'src/engine/core-modules/feature-flag/feature-flag.entity';
 import { FileUploadModule } from 'src/engine/core-modules/file/file-upload/file-upload.module';
 import { AppTokenService } from 'src/engine/core-modules/app-token/services/app-token.service';
@@ -69,7 +69,7 @@ const jwtModule = JwtModule.registerAsync({
     VerifyAuthController,
   ],
   providers: [
-    SignUpService,
+    SignInUpService,
     AuthService,
     TokenService,
     JwtAuthStrategy,
diff --git a/packages/twenty-server/src/engine/core-modules/auth/auth.resolver.ts b/packages/twenty-server/src/engine/core-modules/auth/auth.resolver.ts
index 96126b0e3..610f45cdc 100644
--- a/packages/twenty-server/src/engine/core-modules/auth/auth.resolver.ts
+++ b/packages/twenty-server/src/engine/core-modules/auth/auth.resolver.ts
@@ -97,7 +97,7 @@ export class AuthResolver {
 
   @Mutation(() => LoginToken)
   async signUp(@Args() signUpInput: SignUpInput): Promise<LoginToken> {
-    const user = await this.authService.signUp(signUpInput);
+    const user = await this.authService.signInUp(signUpInput);
 
     const loginToken = await this.tokenService.generateLoginToken(user.email);
 
diff --git a/packages/twenty-server/src/engine/core-modules/auth/controllers/google-auth.controller.ts b/packages/twenty-server/src/engine/core-modules/auth/controllers/google-auth.controller.ts
index d81ba1815..447a65af1 100644
--- a/packages/twenty-server/src/engine/core-modules/auth/controllers/google-auth.controller.ts
+++ b/packages/twenty-server/src/engine/core-modules/auth/controllers/google-auth.controller.ts
@@ -28,7 +28,7 @@ export class GoogleAuthController {
     const { firstName, lastName, email, picture, workspaceInviteHash } =
       req.user;
 
-    const user = await this.authService.signUp({
+    const user = await this.authService.signInUp({
       email,
       firstName,
       lastName,
diff --git a/packages/twenty-server/src/engine/core-modules/auth/services/auth.service.spec.ts b/packages/twenty-server/src/engine/core-modules/auth/services/auth.service.spec.ts
index 4b9bc4da3..b15cdec24 100644
--- a/packages/twenty-server/src/engine/core-modules/auth/services/auth.service.spec.ts
+++ b/packages/twenty-server/src/engine/core-modules/auth/services/auth.service.spec.ts
@@ -7,7 +7,7 @@ import { Workspace } from 'src/engine/core-modules/workspace/workspace.entity';
 import { User } from 'src/engine/core-modules/user/user.entity';
 import { EnvironmentService } from 'src/engine/integrations/environment/environment.service';
 import { EmailService } from 'src/engine/integrations/email/email.service';
-import { SignUpService } from 'src/engine/core-modules/auth/services/sign-up.service';
+import { SignInUpService } from 'src/engine/core-modules/auth/services/sign-in-up.service';
 import { AppToken } from 'src/engine/core-modules/app-token/app-token.entity';
 
 import { AuthService } from './auth.service';
@@ -29,7 +29,7 @@ describe('AuthService', () => {
           useValue: {},
         },
         {
-          provide: SignUpService,
+          provide: SignInUpService,
           useValue: {},
         },
         {
diff --git a/packages/twenty-server/src/engine/core-modules/auth/services/auth.service.ts b/packages/twenty-server/src/engine/core-modules/auth/services/auth.service.ts
index 0f9b301a2..f2905a6f8 100644
--- a/packages/twenty-server/src/engine/core-modules/auth/services/auth.service.ts
+++ b/packages/twenty-server/src/engine/core-modules/auth/services/auth.service.ts
@@ -30,7 +30,7 @@ import { UserService } from 'src/engine/core-modules/user/services/user.service'
 import { EnvironmentService } from 'src/engine/integrations/environment/environment.service';
 import { EmailService } from 'src/engine/integrations/email/email.service';
 import { UpdatePassword } from 'src/engine/core-modules/auth/dto/update-password.entity';
-import { SignUpService } from 'src/engine/core-modules/auth/services/sign-up.service';
+import { SignInUpService } from 'src/engine/core-modules/auth/services/sign-in-up.service';
 import { AuthorizeAppInput } from 'src/engine/core-modules/auth/dto/authorize-app.input';
 import { AuthorizeApp } from 'src/engine/core-modules/auth/dto/authorize-app.entity';
 import {
@@ -51,7 +51,7 @@ export class AuthService {
   constructor(
     private readonly tokenService: TokenService,
     private readonly userService: UserService,
-    private readonly signUpService: SignUpService,
+    private readonly signInUpService: SignInUpService,
     @InjectRepository(Workspace, 'core')
     private readonly workspaceRepository: Repository<Workspace>,
     @InjectRepository(User, 'core')
@@ -80,7 +80,7 @@ export class AuthService {
     return user;
   }
 
-  async signUp({
+  async signInUp({
     email,
     password,
     workspaceInviteHash,
@@ -95,7 +95,7 @@ export class AuthService {
     workspaceInviteHash?: string | null;
     picture?: string | null;
   }) {
-    return await this.signUpService.signUp({
+    return await this.signInUpService.signInUp({
       email,
       password,
       firstName,
diff --git a/packages/twenty-server/src/engine/core-modules/auth/services/sign-up.service.spec.ts b/packages/twenty-server/src/engine/core-modules/auth/services/sign-in-up.service.spec.ts
similarity index 84%
rename from packages/twenty-server/src/engine/core-modules/auth/services/sign-up.service.spec.ts
rename to packages/twenty-server/src/engine/core-modules/auth/services/sign-in-up.service.spec.ts
index f453ce7f6..370bfeee8 100644
--- a/packages/twenty-server/src/engine/core-modules/auth/services/sign-up.service.spec.ts
+++ b/packages/twenty-server/src/engine/core-modules/auth/services/sign-in-up.service.spec.ts
@@ -5,17 +5,17 @@ import { HttpService } from '@nestjs/axios';
 import { Workspace } from 'src/engine/core-modules/workspace/workspace.entity';
 import { User } from 'src/engine/core-modules/user/user.entity';
 import { EnvironmentService } from 'src/engine/integrations/environment/environment.service';
-import { SignUpService } from 'src/engine/core-modules/auth/services/sign-up.service';
+import { SignInUpService } from 'src/engine/core-modules/auth/services/sign-in-up.service';
 import { FileUploadService } from 'src/engine/core-modules/file/file-upload/services/file-upload.service';
 import { UserWorkspaceService } from 'src/engine/core-modules/user-workspace/user-workspace.service';
 
-describe('SignUpService', () => {
-  let service: SignUpService;
+describe('SignInUpService', () => {
+  let service: SignInUpService;
 
   beforeEach(async () => {
     const module: TestingModule = await Test.createTestingModule({
       providers: [
-        SignUpService,
+        SignInUpService,
         {
           provide: FileUploadService,
           useValue: {},
@@ -43,7 +43,7 @@ describe('SignUpService', () => {
       ],
     }).compile();
 
-    service = module.get<SignUpService>(SignUpService);
+    service = module.get<SignInUpService>(SignInUpService);
   });
 
   it('should be defined', () => {
diff --git a/packages/twenty-server/src/engine/core-modules/auth/services/sign-up.service.ts b/packages/twenty-server/src/engine/core-modules/auth/services/sign-in-up.service.ts
similarity index 91%
rename from packages/twenty-server/src/engine/core-modules/auth/services/sign-up.service.ts
rename to packages/twenty-server/src/engine/core-modules/auth/services/sign-in-up.service.ts
index 71f0b390c..51f752848 100644
--- a/packages/twenty-server/src/engine/core-modules/auth/services/sign-up.service.ts
+++ b/packages/twenty-server/src/engine/core-modules/auth/services/sign-in-up.service.ts
@@ -16,6 +16,7 @@ import { assert } from 'src/utils/assert';
 import {
   PASSWORD_REGEX,
   hashPassword,
+  compareHash,
 } from 'src/engine/core-modules/auth/auth.util';
 import { User } from 'src/engine/core-modules/user/user.entity';
 import { Workspace } from 'src/engine/core-modules/workspace/workspace.entity';
@@ -24,7 +25,7 @@ import { EnvironmentService } from 'src/engine/integrations/environment/environm
 import { getImageBufferFromUrl } from 'src/utils/image';
 import { UserWorkspaceService } from 'src/engine/core-modules/user-workspace/user-workspace.service';
 
-export type SignUpServiceInput = {
+export type SignInUpServiceInput = {
   email: string;
   password?: string;
   firstName?: string | null;
@@ -34,7 +35,7 @@ export type SignUpServiceInput = {
 };
 
 @Injectable()
-export class SignUpService {
+export class SignInUpService {
   constructor(
     private readonly fileUploadService: FileUploadService,
     @InjectRepository(Workspace, 'core')
@@ -46,14 +47,14 @@ export class SignUpService {
     private readonly environmentService: EnvironmentService,
   ) {}
 
-  async signUp({
+  async signInUp({
     email,
     workspaceInviteHash,
     password,
     firstName,
     lastName,
     picture,
-  }: SignUpServiceInput) {
+  }: SignInUpServiceInput) {
     if (!firstName) firstName = '';
     if (!lastName) lastName = '';
 
@@ -72,17 +73,34 @@ export class SignUpService {
     if (picture) {
       imagePath = await this.uploadPicture(picture);
     }
+    const existingUser = await this.userRepository.findOne({
+      where: {
+        email: email,
+      },
+      relations: ['defaultWorkspace'],
+    });
+
+    if (existingUser && existingUser.passwordHash) {
+      const isValid = await compareHash(
+        password || '',
+        existingUser.passwordHash,
+      );
+
+      assert(isValid, 'Wrong password', ForbiddenException);
+    }
 
     if (workspaceInviteHash) {
-      return await this.signUpOnExistingWorkspace({
+      return await this.signInUpOnExistingWorkspace({
         email,
         passwordHash,
         workspaceInviteHash,
         firstName,
         lastName,
         imagePath,
+        existingUser,
       });
-    } else {
+    }
+    if (!existingUser) {
       return await this.signUpOnNewWorkspace({
         email,
         passwordHash,
@@ -91,15 +109,18 @@ export class SignUpService {
         imagePath,
       });
     }
+
+    return existingUser;
   }
 
-  private async signUpOnExistingWorkspace({
+  private async signInUpOnExistingWorkspace({
     email,
     passwordHash,
     workspaceInviteHash,
     firstName,
     lastName,
     imagePath,
+    existingUser,
   }: {
     email: string;
     passwordHash: string | undefined;
@@ -107,14 +128,8 @@ export class SignUpService {
     firstName: string;
     lastName: string;
     imagePath: string | undefined;
+    existingUser: User | null;
   }) {
-    const existingUser = await this.userRepository.findOne({
-      where: {
-        email: email,
-      },
-      relations: ['defaultWorkspace'],
-    });
-
     const workspace = await this.workspaceRepository.findOneBy({
       inviteHash: workspaceInviteHash,
     });
@@ -181,17 +196,6 @@ export class SignUpService {
     lastName: string;
     imagePath: string | undefined;
   }) {
-    const existingUser = await this.userRepository.findOne({
-      where: {
-        email: email,
-      },
-      relations: ['defaultWorkspace'],
-    });
-
-    if (existingUser) {
-      assert(!existingUser, 'This user already exists', ForbiddenException);
-    }
-
     assert(
       !this.environmentService.get('IS_SIGN_UP_DISABLED'),
       'Sign up is disabled',