Which Mailtrap service should your app connect to?

Use Email Sandbox to catch test messages in a Mailtrap inbox. Use Email Live Sending when the message should reach a real address. The two connections have separate settings and plans.

For live sending, add a sending domain, publish the records Mailtrap provides in your domain settings, and wait for domain verification and the compliance check before using its live sending credentials.

How can you check a receipt before anyone receives it?

Route one fictional receipt from a disposable copy of the app into a sandbox you control. A captured message lets you check what the app prepared. Live delivery and inbox placement still need their own checks.

Confirm where the app hands off mail
Compare the app’s actual host and credentials with the sandbox Integration tab. If you use an API, confirm the sandbox endpoint and inbox ID. Before triggering the test, check the outgoing message’s actual To, Cc and Bcc fields. To must contain only a reserved example address such as buyer@example.com. Cc and Bcc must be empty. Check that automatic forwarding has no active rules, that no fallback path uses a live sender, and that any connected notifications or callbacks stay in the test setup. If you cannot verify the route or recipient fields, sketch the expected message on paper.
Inspect one receipt
Use a made-up order and a reserved example address, then open the captured message in the sandbox. Compare the amount and order number with the fixture. Compare the displayed recipient, subject and plain-text version with what the app was meant to prepare. Avoid forwarding the message to a real address.
Record what the check covered
If the receipt is missing, compare the app’s settings and the sandbox’s limits before trying again. If it appears, you have evidence about the app’s handoff and message content. The sandbox does not tell you where a live inbox will place it.

Where do you check a real email that went missing?

Open Email Logs in the live sending area and find the message. Delivered means the receiving mail service accepted it. A soft bounce is a temporary failure and can be retried by Mailtrap. A permanent bounce ends the delivery attempt.

Check the event history for the mailbox response or whether the address is on that sending domain’s suppression list. That list records addresses Mailtrap should skip. You can export the suppression list. If you need a separate delivery history, set up your own record of sending events in advance using webhooks, which are notifications sent to an address your app controls.

Why do sandbox tests and live messages have different limits?

Email Sandbox counts test messages separately. Its Free plan lists 50 tests per month and space for 10 messages in one sandbox. Live Sending Free lists 4,000 emails per month and 150 per day. Those are separate from the sandbox quota.

You can retrieve sandbox message content such as text and raw HTML through the sandbox API. That gives you a way to save a test example. Keep your own template files and delivery history separately if you plan to change senders.