Solutions / Transactional email

Transactional email API for apps and stores

Send order confirmations, OTPs, password resets and invoices from your app or website through a simple REST API, with the same deliverability tools as your campaigns.

At a glance

Ideal for ecommerce stores, SaaS products, booking systems and internal tools.

Overview

System emails your customers actually receive

An OTP that lands in spam or an order confirmation that never arrives costs you sales and support time. Transactional emails need fast, reliable delivery from an authenticated domain.

GO MAILBOX gives your developers a REST API to send these emails and manage subscribers. You choose the route: our managed servers, or your own SMTP or Amazon SES account, so important system mail is never stuck behind a big marketing send.

How it works

Authenticate your domain

Add SPF, DKIM and DMARC records so mailbox providers trust your mail.

Create an API key

Generate a key for your app or website in the dashboard.

Send from your code

Call the REST API to send emails or add and update subscribers.

Monitor delivery

Track delivered, bounced and failed messages in reports.

Key capabilities

Everything developers need

Reliable sending with as little setup as possible.

REST API

Send emails and manage subscribers with standard HTTP requests.

Choice of route

Use managed servers or plug in your own SMTP or Amazon SES.

Authenticated sending

One-click domain verification and DKIM key generation.

Domain authentication →

Automatic suppression

Hard bounces and complaints are suppressed so they are not mailed again.

2FA and roles

Secure the account with two-factor authentication and role-based access.

Delivery reports

See what was delivered, opened and bounced.

View reporting →
Who uses this

Emails you can send through the API

Common transactional messages.

Order and shipping updates

Confirmations, dispatch notices and delivery updates.

OTPs and password resets

Login codes and reset links that must arrive fast.

Invoices and receipts

Payment receipts, invoices and renewal reminders.

Alerts and notifications

Account alerts, booking reminders and status changes.

FAQ

Transactional email questions

Transactional Email FAQ

  • What are transactional emails?

    One-to-one emails triggered by an action, such as order confirmations, OTPs, password resets and invoices.

  • How do I send transactional emails?

    Use the GO MAILBOX REST API from your website or app. The API also lets you add and update subscribers.

  • Can I keep transactional and marketing mail separate?

    Yes. You can route them through different servers or SMTP connections so marketing traffic does not affect important system emails.

Start today

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