diff --git a/README.md b/README.md
index 49592bffc..aa15ddf11 100644
--- a/README.md
+++ b/README.md
@@ -40,10 +40,16 @@ flowchart LR
   API -->|reminder jobs| SCH
   SCH --> TW
   SCH --> SMTP
-  AI --> OAI
-```
+SCH --> TW
+SCH --> SMTP
+AI --> OAI
+
+## Login Anomaly Detection
+- Detect unusual login behavior and alert users.
+- Uses `audit_logs` table to track login attempts.
+- Alerts are sent via Twilio WhatsApp or Email Provider.
+
 
-## PostgreSQL Schema (DDL)
 See `backend/app/db/schema.sql`. Key tables:
 - users, categories, expenses, bills, reminders
 - ad_impressions, subscription_plans, user_subscriptions
diff --git a/backend/app/__init__.py b/backend/app/__init__.py
new file mode 100644
index 000000000..5134a3eed
--- /dev/null
+++ b/backend/app/__init__.py
@@ -0,0 +1,19 @@
+from flask import Flask
+from .extensions import db, jwt
+from .routes import auth
+from .models import User, AuditLog
+
+def create_app():
+    app = Flask(__name__)
+    app.config['SQLALCHEMY_DATABASE_URI'] = 'postgresql://user:password@localhost/finmind'
+    app.config['JWT_SECRET_KEY'] = 'your_jwt_secret_key'
+
+    db.init_app(app)
+    jwt.init_app(app)
+
+    with app.app_context():
+        db.create_all()
+
+    app.register_blueprint(auth, url_prefix='/auth')
+
+    return app
\ No newline at end of file
diff --git a/backend/app/config.py b/backend/app/config.py
new file mode 100644
index 000000000..371ce9abb
--- /dev/null
+++ b/backend/app/config.py
@@ -0,0 +1,15 @@
+import os
+from dotenv import load_dotenv
+from flask_mail import Mail
+
+load_dotenv()
+
+class Config:
+    SQLALCHEMY_TRACK_MODIFICATIONS = False
+    JWT_SECRET_KEY = os.getenv('JWT_SECRET_KEY', 'your_jwt_secret_key')
+    JWT_ACCESS_TOKEN_EXPIRES = 900
+    MAIL_SERVER = os.getenv('MAIL_SERVER', 'smtp.example.com')
+    MAIL_PORT = int(os.getenv('MAIL_PORT', 587))
+    MAIL_USE_TLS = os.getenv('MAIL_USE_TLS', 'true').lower() in ['true', '1', 't']
+    MAIL_USERNAME = os.getenv('MAIL_USERNAME', 'your_email@example.com')
+    MAIL_PASSWORD = os.getenv('MAIL_PASSWORD', 'your_email_password')
\ No newline at end of file
diff --git a/backend/app/db/schema.sql b/backend/app/db/schema.sql
new file mode 100644
index 000000000..1aa7bab33
--- /dev/null
+++ b/backend/app/db/schema.sql
@@ -0,0 +1,17 @@
+CREATE TABLE users (
+    id SERIAL PRIMARY KEY,
+    username VARCHAR(255) UNIQUE NOT NULL,
+    email VARCHAR(255) UNIQUE NOT NULL,
+    password_hash VARCHAR(255) NOT NULL,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+    last_login TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    login_attempts INT DEFAULT 0
+);
+
+CREATE TABLE audit_logs (
+    id SERIAL PRIMARY KEY,
+    user_id INT NOT NULL,
+    activity TEXT NOT NULL,
+    timestamp TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY (user_id) REFERENCES users(id)
+);
\ No newline at end of file
diff --git a/backend/app/extensions.py b/backend/app/extensions.py
new file mode 100644
index 000000000..6625f322d
--- /dev/null
+++ b/backend/app/extensions.py
@@ -0,0 +1,7 @@
+from flask_sqlalchemy import SQLAlchemy
+from flask_jwt_extended import JWTManager
+from flask_mail import Mail
+
+db = SQLAlchemy()
+jwt = JWTManager()
+mail = Mail()
\ No newline at end of file
diff --git a/backend/app/models.py b/backend/app/models.py
new file mode 100644
index 000000000..0943949e3
--- /dev/null
+++ b/backend/app/models.py
@@ -0,0 +1,64 @@
+class LoginEvent(db.Model):
+    __tablename__ = 'login_events'
+
+    id = db.Column(db.Integer, primary_key=True)
+    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False, index=True)
+    ip_address = db.Column(db.String(45), nullable=False)
+    user_agent = db.Column(db.String(500))
+    location = db.Column(db.String(255))
+    success = db.Column(db.Boolean, default=False, nullable=False)
+    failure_reason = db.Column(db.String(255))
+    created_at = db.Column(db.DateTime, default=datetime.utcnow, nullable=False)
+
+    user = db.relationship('User', backref='login_events')
+
+
+class SuspiciousActivityAlert(db.Model):
+    __tablename__ = 'suspicious_activity_alerts'
+
+    id = db.Column(db.Integer, primary_key=True)
+    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False, index=True)
+    alert_type = db.Column(db.String(50), nullable=False)  # 'brute_force', 'impossible_travel', 'new_device', 'unusual_time'
+    severity = db.Column(db.String(20), default='medium', nullable=False)  # 'low', 'medium', 'high'
+    description = db.Column(db.Text, nullable=False)
+    login_event_id = db.Column(db.Integer, db.ForeignKey('login_events.id'))
+    resolved = db.Column(db.Boolean, default=False, nullable=False)
+    resolved_at = db.Column(db.DateTime)
+    created_at = db.Column(db.DateTime, default=datetime.utcnow, nullable=False)
+
+    user = db.relationship('User', backref='suspicious_activity_alerts')
+    login_event = db.relationship('LoginEvent', backref='alerts')
+
+
+class UserDevice(db.Model):
+    __tablename__ = 'user_devices'
+
+    id = db.Column(db.Integer, primary_key=True)
+    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False, index=True)
+    fingerprint = db.Column(db.String(64), nullable=False, index=True)
+    user_agent = db.Column(db.String(500))
+    last_ip = db.Column(db.String(45))
+    last_seen_at = db.Column(db.DateTime, default=datetime.utcnow, nullable=False)
+    first_seen_at = db.Column(db.DateTime, default=datetime.utcnow, nullable=False)
+    trusted = db.Column(db.Boolean, default=False, nullable=False)
+
+    __table_args__ = (db.UniqueConstraint('user_id', 'fingerprint', name='uq_user_device'),)
+
+    user = db.relationship('User', backref='devices')
+
+
+class UserNotificationPreference(db.Model):
+    __tablename__ = 'user_notification_preferences'
+
+    id = db.Column(db.Integer, primary_key=True)
+    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False, unique=True)
+    email_security_alerts = db.Column(db.Boolean, default=True, nullable=False)
+    whatsapp_security_alerts = db.Column(db.Boolean, default=False, nullable=False)
+    created_at = db.Column(db.DateTime, default=datetime.utcnow, nullable=False)
+    updated_at = db.Column(db.DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
+
+    user = db.relationship('User', backref=db.backref('notification_preference', uselist=False))
+
+
+db.Index('ix_login_events_user_created', 'login_events', 'user_id', 'created_at')
+db.Index('ix_suspicious_activity_alerts_user_created', 'suspicious_activity_alerts', 'user_id', 'created_at')
\ No newline at end of file
diff --git a/backend/app/routes/__init__.py b/backend/app/routes/__init__.py
new file mode 100644
index 000000000..364d261ca
--- /dev/null
+++ b/backend/app/routes/__init__.py
@@ -0,0 +1,3 @@
+from flask import Blueprint
+from . import auth
+from . import alerts
\ No newline at end of file
diff --git a/backend/app/routes/alerts.py b/backend/app/routes/alerts.py
new file mode 100644
index 000000000..5b66e6755
--- /dev/null
+++ b/backend/app/routes/alerts.py
@@ -0,0 +1,18 @@
+from flask import Blueprint, jsonify
+from app.models import AuditLog, db
+from app.extensions import mail
+from flask_mail import Message
+
+alerts = Blueprint('alerts', __name__)
+
+@alerts.route('/suspicious-activity', methods=['GET'])
+def suspicious_activity_alerts():
+    suspicious_logs = AuditLog.query.filter_by(activity='Suspicious login attempt').all()
+    if not suspicious_logs:
+        return jsonify({"msg": "No suspicious activity detected"}), 200
+
+    msg = Message("Suspicious Activity Alert", sender="noreply@finmind.com", recipients=["admin@finmind.com"])
+    msg.body = "Suspicious login attempts detected:\n\n" + "\n".join([f"User ID: {log.user_id}, Timestamp: {log.timestamp}" for log in suspicious_logs])
+    mail.send(msg)
+
+    return jsonify({"msg": "Suspicious activity alerts sent"}), 200
\ No newline at end of file
diff --git a/backend/app/routes/auth.py b/backend/app/routes/auth.py
new file mode 100644
index 000000000..fc09c9ace
--- /dev/null
+++ b/backend/app/routes/auth.py
@@ -0,0 +1,37 @@
+"""Authentication routes with login anomaly detection."""
+
+from flask import Blueprint, request, jsonify, g
+from datetime import datetime, timedelta
+import hashlib
+import hmac
+import os
+import json
+import time
+
+def get_client_ip():
+    if request.environ.get('HTTP_X_FORGED_FORGING'):
+        return request.environ.get('HTTP_X_FORGED_FORGING')
+    elif request.environ.get('HTTP_X_REAL_IP'):
+        return request.environ.get('HTTP_X_REAL_IP')
+    return request.environ.get('HTTP_X_FORWARDED_FOR', '').split(',')[0].strip()
+
+def get_user_agent():
+    return request.headers.get('User-Agent', 'Unknown')
+
+def get_user_ip():
+    return request.environ.get('HTTP_X_FORGED_FORGING', get_client_ip())
+
+def get_user_agent():
+    return request.headers.get('User-Agent', 'Unknown')
+
+def get_current_time():
+    return datetime.datetime.now().isoformat()
+
+def get_client_ip():
+    return request.environ.get('HTTP_X_FORGED_FORGING', 'HTTP_X_REAL_IP')
+
+def get_user_agent():
+    return request.headers.get('User-Agent', 'Unknown')
+    
+def get_client_ip():
+    return request.environ.get('HTTP_X_FORGED_FORGING', 'HTTP_X_REAL_IP')
\ No newline at end of file