Production checklist

Verify your sending domain

Add the DNS records shown in the dashboard and wait until every required record is verified.

Create Project API tokens per integration

Create a separate Project API token for each app, worker, or environment. Store each token as LETTERMINT_PROJECT_TOKEN.

Confirm the default outbound route

New projects can create transactional and broadcast routes. Confirm which transactional or broadcast route is the default before omitting route from send requests.

Send test-address scenarios

Use Lettermint test addresses to simulate deliveries, soft bounces, hard bounces, and spam complaints without affecting sender reputation.

Use idempotency for retried sends

Add an Idempotency-Key for important transactional sends. Keys are scoped per project and valid for 24 hours.

Set suppression policy

Decide when to use team, project, and route-level suppressions. Make sure support and compliance teams know spam complaint suppressions cannot be removed through normal self-service.

Configure webhooks and signature verification

Subscribe each route to the events your app needs, store the webhook signing secret, and verify signatures before processing payloads.

Review tracking and privacy choices

Enable open and click tracking only where appropriate. For critical security emails, consider leaving tracking disabled.

Set billing and spend controls

Review your plan, monthly included email volume, and spend limit behavior before production volume ramps up.

Monitor delivery

Use Email Activity, webhooks, and Team API message endpoints to watch delivery, bounces, complaints, and delivery insights.