February 2026

Lettr Is Live

An email API built for the Laravel ecosystem, from the team behind Topol.io and DMARCeye.

Setting up transactional email in a new project means wiring a mail driver, picking a service, wrestling DNS records and designing templates in some external tool. Then the visibility runs out: nothing shows what your application is actually sending, whether the welcome emails are landing in inboxes or spam folders, or that something broke three days ago. We wanted something that belonged in the ecosystem instead of sitting next to it.

Install the package, add an API key, and the first email goes out. Templates can be built in the drag-and-drop editor — we brought over the best parts of Topol.io — or written as HTML, whichever you would rather. Merge tags fill them in per recipient, and saved sections shared across templates propagate everywhere they are used when you edit one.

Sending domains walk you through the DNS. Lettr identifies your DNS provider from the nameservers and shows the records next to its name, and for Cloudflare it can generate a one-click setup link rather than making you type anything. Records are re-checked rather than trusted once, with a short grace period and repeated failures required before a domain is marked broken, so one slow lookup does not undo a verified domain. You can also point your own domain at the storage holding the images your emails use.

There is more than one way in. Beyond the REST API there is an SMTP relay, for applications that already speak SMTP and are not going to be rewritten, and an MCP server so an AI assistant can work with your templates and analytics directly.

Everything you send is visible. The dashboard covers delivery and open rates with trends; a tag on a send — filled in automatically from the template slug if you do not set one — groups your analytics by the kind of email it was, so password resets and invoices can be told apart without any extra work. The event log goes down to individual messages and what happened to them. Alerts cover the things that stop sends: approaching your plan limit, and a domain that is unverified or blocked.

API keys can be restricted to a set of IP addresses, and every send answers with your remaining quota in the response headers. Requests are throttled at three a second across all of a team's keys.

The free plan is genuinely free, with no card required: 3,000 emails a month, and 100 a day. Paid plans start at 50,000 a month.

composer require lettr/lettr-laravel
php artisan lettr:init

Sandbox API Keys

A key can be created as Sandbox instead of Live, and needs no verified sending domain to work.

A sandbox send costs nothing and reaches nobody: every recipient is replaced with your own address, cc and bcc are dropped, and it skips billing and your daily limit entirely. Sandbox keys are throttled separately and refused by every write endpoint, so nothing you do with one can change your account. The sends are readable back through the same endpoints as everything else.

Scheduled Sending Over The API

Schedule a send, look it up, and cancel it before it goes.

scheduled_at has to be at least five minutes and at most three days ahead. Scheduling reuses the entire ordinary send path, so domain checks, quota and counters all apply exactly as they do to an immediate send.

curl -X POST https://app.lettr.com/api/emails/scheduled \
  -H "Authorization: Bearer $LETTR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "from": "hello@example.com",
    "to": ["jane@example.com"],
    "template_slug": "trial-ending",
    "scheduled_at": "2026-03-01T09:00:00Z"
  }'

Manage Webhooks Over The API

Webhooks stopped being something you could only create in the interface — they can now be created, updated and deleted from code.

An update is partial, so you can change a name, a target, an auth type, the events it is subscribed to or whether it is active, without resending the rest.

Query Events Across Every Email

A new endpoint searches events across all of your mail rather than one message at a time, filtering by event type, recipient, date range and bounce class.

The events themselves gained real shapes at the same time. Eighteen types — delivery, bounce, delay, click, open, spam complaint, unsubscribe, policy rejection and the rest — each carry their own fields, with the user agent parsed out into browser, operating system and device, and location data alongside. Opens that a mailbox provider prefetched are labelled as such in the event log. from and to were added to both the list and the detail response.

Loops In Substitution Data

data used to be a flat map of strings. It now takes any scalar, and arrays of objects.

Which means order lines, itemised receipts and digest lists can be looped over inside the template instead of being rendered into a string before you send them. Objects nested more than one level deep are rejected, and the message names the key that caused it.

curl -X POST https://app.lettr.com/api/emails \
  -H "Authorization: Bearer $LETTR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "from": "orders@example.com",
    "to": ["jane@example.com"],
    "template_slug": "order-confirmation",
    "data": {
      "first_name": "Jane",
      "items": [
        { "name": "Keyboard", "qty": 1, "price": "89.00" },
        { "name": "Cable", "qty": 2, "price": "12.00" }
      ]
    }
  }'