Email

Better Auth uses email for verification and OTP-based two-factor authentication. Some routes also use explicit plugin callbacks for delivery. You configure an email provider to handle the flows that call EmailProvider directly.

Email Provider Trait

Better Auth defines an EmailProvider trait that you implement to integrate with your email service:

#[async_trait]
pub trait EmailProvider: Send + Sync {
    async fn send_email(
        &self,
        to: &str,
        subject: &str,
        body: &str,
    ) -> Result<(), Box<dyn std::error::Error>>;
}

Setup

Using a Custom Provider

use better_auth::email::EmailProvider;

struct SmtpEmailProvider {
    // your SMTP client configuration
}

#[async_trait::async_trait]
impl EmailProvider for SmtpEmailProvider {
    async fn send_email(
        &self,
        to: &str,
        subject: &str,
        body: &str,
    ) -> Result<(), Box<dyn std::error::Error>> {
        // Send email using your SMTP library
        Ok(())
    }
}

let auth = BetterAuth::new(config)
    .database(database)
    .email_provider(SmtpEmailProvider { /* ... */ })
    .build()
    .await?;

Console Provider (Development)

For development, you can use a simple provider that logs emails to the console:

struct ConsoleEmailProvider;

#[async_trait::async_trait]
impl EmailProvider for ConsoleEmailProvider {
    async fn send_email(
        &self,
        to: &str,
        subject: &str,
        body: &str,
    ) -> Result<(), Box<dyn std::error::Error>> {
        println!("=== Email to: {} ===", to);
        println!("Subject: {}", subject);
        println!("{}", body);
        println!("==================");
        Ok(())
    }
}

When Emails Are Sent

Better Auth sends emails in the following scenarios:

Email Verification

When require_email_verification is enabled on the EmailPasswordPlugin, a verification email is sent after sign-up:

Subject: Email verification
Content: Contains a verification URL with a token
Token expiry: Configurable, typically 24 hours

See Email Verification for details.

Password Reset

POST /request-password-reset does not use EmailProvider directly. To enable that route, configure PasswordManagementPlugin::send_reset_password(...).

See Password Management for the route-specific sender setup.

Two-Factor OTP

When using the OTP method of the TwoFactorPlugin:

Subject: Your one-time password
Content: Contains a 6-digit OTP code
Code expiry: 5 minutes

See Two-Factor Authentication for details.

Email Content

Email content is generated internally by Better Auth. The default templates produce simple text-based emails. The content varies by email type:

Email Type	Key Content
Verification	Verification URL with token
Password Reset	Reset URL with token
OTP	6-digit numeric code

Configuration

Email-related settings are spread across the plugins that use email:

Email Verification Config

EmailVerificationPlugin::new()
    .send_on_signup(true)         // Auto-send verification email on sign-up
    .auto_signin_after_verify(true) // Create session after email verification

Password Reset Config

PasswordManagementPlugin::new()
    // Password reset is enabled when the plugin is registered

2FA OTP Config

TwoFactorPlugin::new()
    // OTP emails are sent via the configured email provider

Error Handling

If no email provider is configured, any operation that requires sending an email will return an error:

{
  "code": "EMAIL_PROVIDER_NOT_CONFIGURED",
  "message": "Email provider is not configured"
}

Make sure to configure an email provider if you use any email-dependent features.