How to Create User Registration and Login for Your SaaS

What the Platform Provides

When you set up a customer portal on your domain, the authentication system is ready to use immediately. Your customers see a branded login page at your domain, not a third-party URL. The system handles:

• Registration: Email and password form that creates a new account with a unique account ID. All account data structures are initialized automatically.
• Login: Email/password verification with session creation. Sessions are stored in DynamoDB with configurable timeout.
• Password recovery: Email-based reset flow with time-limited tokens.
• Session persistence: Users stay logged in across page loads. Sessions expire after the configured timeout period.
• Sub-user accounts: Account owners can invite team members who get their own login credentials but share the account's data.

How Registration Works

Customizing the Registration Flow

For most SaaS products, the default registration flow works out of the box. If you need customizations, common options include:

• Additional registration fields: Collect company name, phone number, or industry during signup. These get stored in the customer's data record.
• Invite-only registration: Disable public registration and only allow signups through invitation links you send manually.
• Free trial setup: Automatically give new accounts a starting credit balance or enable specific features for a trial period.
• Welcome email: Send an automated welcome email after registration using the email automation system.

Security Considerations

The platform handles core security automatically:

• Passwords are hashed, never stored in plain text
• Sessions expire after configurable timeouts
• All communication runs over HTTPS with automatic SSL certificates
• Account data is isolated by partition key, making cross-account data leaks structurally impossible
• API key authentication is available for programmatic access alongside session-based web login

For additional security, you can enable IP allowlisting so accounts can only be accessed from approved IP addresses. This is useful for B2B SaaS products where customers want to restrict access to their office networks.

Handling Multiple User Types

If your SaaS has different types of users (for example, a marketplace with both buyers and sellers, or a helpdesk with both support agents and customers), you have two approaches:

• Role-based within one account: All users register the same way and get assigned different roles that control their permissions. This works well when users share data (like a helpdesk where agents see the same tickets). See How to Structure SaaS User Accounts and Permissions.
• Separate account types: Different registration forms that create accounts with different default configurations. This works for marketplace models where buyers and sellers have fundamentally different interfaces.