Laravel Helo Email

Send Laravel mail through Helo's API, and call the rest of Helo's API from your app. Set your mailer to helo, add an API key, and your Mailables, notifications, and Mail::raw calls send through Helo.

Install

composer require stechstudio/laravel-helo-email

Add these lines to .env:

MAIL_MAILER=helo
HELO_API_KEY=...
HELO_CHANNEL_ID=...

A Helo API key covers either all channels or one. With a key for all channels, HELO_CHANNEL_ID picks the channel to send through. With a key for one channel, sending works without it, but set it anyway: Helo requires a channel ID for suppressions, broadcast lists, and new webhooks.

You don't need to change config/mail.php. The package adds a helo mailer when your config doesn't define one.

To change the defaults, publish the config:

php artisan vendor:publish --tag=helo-config

A missing API key fails on the first request, not at boot, so config:cache and test suites that never send keep working.

Several channels or mail types

Add a mailer to config/mail.php for each extra channel or mail type. Settings you put there override config/helo.php. A key limited to one channel can't reach another, so a mailer for another channel needs a key for it, unless your main key covers all channels.

'helo-newsletter' => [
    'transport' => 'helo',
    'key' => env('HELO_NEWSLETTER_API_KEY'),
    'channel_id' => env('HELO_NEWSLETTER_CHANNEL_ID'),
    'mail_type' => 'broadcast',
],

To send broadcast mail through your main channel, leave out key and channel_id and set only mail_type.

Mail::mailer('helo-newsletter')->to($user)->send(new Newsletter);

Sending options

Tags and metadata. Laravel's tag() and metadata() become Helo's tags and metadata:

(new OrderShipped($order))->tag('receipt')->metadata('order_id', $order->id);

Tracking. Turn open or link tracking on or off for one message:

$this->withSymfonyMessage(function (Email $message) {
    $message->getHeaders()->addTextHeader('X-Helo-TrackOpens', 'true');
    $message->getHeaders()->addTextHeader('X-Helo-TrackLinks', 'false');
});

Safe retries. Add an X-Helo-Idempotency-Key header with a value that's unique to the message, such as order-42-receipt. Helo sends a message with a given key only once, so this is the only safe way to retry a send that may have gone through.

A retry must send exactly the same request, or Helo rejects the key. The transport leaves out the Message-ID header and gives inline images stable IDs, so rebuilding the same email gives the same request.

Broadcast mail. Set mail_type to broadcast for marketing and bulk mail. Helo adds its own unsubscribe link and List-Unsubscribe headers to every broadcast message, and you can't point them at your own page. Put {{{ helo: unsubscribe }}} in your template to choose where the link appears. Without it, Helo adds the link at the end. Transactional mail gets no link.

After sending

$sent->getMessageId() returns Helo's message ID, the same ID Helo's webhooks carry.

HeloResult::from($sent) returns the full result, including any recipients Helo skipped because they're suppressed:

use STS\HeloEmail\HeloResult;

$sent = Mail::to($user)->send(new Welcome);
$result = HeloResult::from($sent); // null if the mail didn't go through Helo

$result->messageId;
$result->status;       // "accepted" or "delayed"
$result->suppressions; // ["gone@example.com"]

The package also fires STS\HeloEmail\Events\HeloMessageSent after each send, with the sent message and the result.

API client

The Helo facade covers the rest of Helo's API. Methods take named arguments that match Helo's parameter names.

use STS\HeloEmail\Facades\Helo;

// Send
Helo::send()->transactional([
    'from' => ['email' => 'hello@example.com'],
    'to' => [['email' => 'a@example.com']],
    'subject' => 'Hi',
    'html' => '<p>Hi</p>',
], idempotencyKey: 'welcome-42');
Helo::send()->broadcastMessage($message);
Helo::send()->transactionalBatch([$first, $second]);
Helo::send()->broadcast($broadcast);

// Suppressions: one list per channel and mail type
Helo::suppressions()->list(mailType: 'broadcast', reason: 'bounce');
Helo::suppressions()->add(['a@example.com'], mailType: 'broadcast');
Helo::suppressions()->remove(['a@example.com']);

// Webhooks
$webhook = Helo::webhooks()->create('https://app.example/webhooks/helo', ['email-delivered', 'email-bounced']);
$webhook->payloadSigningKey;
Helo::webhooks()->list();
Helo::webhooks()->update($id, ['enabled' => false]);
Helo::webhooks()->regenerateSigningKey($id);
Helo::webhooks()->delete($id);

// Channels
Helo::channels()->create('ABC Construction', trackOpens: true);
Helo::channels()->list(name: 'ABC');
Helo::channels()->update($id, ['name' => 'ABC Builders']);

// Domains
Helo::domains()->create('mail.example.com', channelIds: [$channelId]);
$check = Helo::domains()->verify($id);
$check->domainKeyActive['status'];
Helo::domains()->rotateKey($id);

// Activity
Helo::activity()->events(recipient: 'a@example.com', eventTypes: ['email-bounced']);
Helo::activity()->messages(status: 'sent', tags: ['receipt']);
Helo::activity()->message($messageId)->events;

// Broadcasts
Helo::broadcasts()->list(status: 'completed');
Helo::broadcasts()->failures($broadcastId);
Helo::broadcasts()->suppressions($broadcastId);

// Statistics
Helo::statistics()->daily('2026-10-01', '2026-10-31', timezone: 'America/New_York');
Helo::statistics()->hourly(now()->subDay(), now());
Helo::statistics()->totals(now()->startOfMonth(), now());

Every resource also has get, update, and delete where Helo supports them.

Responses. A single object is a Response. Read a field as $domain->status or $domain['status']. Fields Helo adds later pass through. Key fields:

A batch send or suppression change that Helo rejects for one address comes back inside a successful response. Check each suppression result's success, or each batch response's status. A single send that Helo rejects throws.

Paging. A list returns a Page with the first page of items. Call ->lazy() to walk every page; it fetches the next page only when the loop needs it.

foreach (Helo::suppressions()->list(mailType: 'broadcast')->lazy() as $suppression) {
    $suppression->email;
}

Other channels. Helo::forChannel($id, $key) returns a client for another channel, for apps that send for many customers. If your key covers all channels, the channel ID is enough. If each channel has its own key, pass that key too.

Helo::forChannel($tenant->helo_channel_id, $tenant->helo_api_key)->suppressions()->list();

Suppressions, broadcast lists, and new webhooks need a channel ID, even with a key for one channel. Pass channelId:, use forChannel(), or set HELO_CHANNEL_ID.

New parameters. Methods that take named parameters also accept extra:, which is merged into the request. A new Helo parameter works before this package adds it.

Helo::suppressions()->list(extra: ['newFilter' => 'value']);

Errors

A failed request throws STS\HeloEmail\HeloException:

• status(): the HTTP status
• errorCode(): Helo's error code, such as recipients_suppressed
• detail(): Helo's error message
• response(): the Laravel HTTP response

Connection failures throw Laravel's ConnectionException.

When Laravel sends mail, any failure becomes a Symfony TransportException, so Laravel's failover mailer works. The package never retries a send on its own, because a retry could deliver twice. Use an idempotency key to retry safely.

Testing your app

Fake Helo's API with Laravel's HTTP fake:

Http::fake([
    'api.helohq.com/*' => Http::response(['status' => 'accepted', 'messageId' => 'test-id']),
]);

Mail::to('a@example.com')->send(new Welcome);

Http::assertSent(fn ($request) => $request->url() === 'https://api.helohq.com/send/transactional');

Not included

• Webhooks. This package doesn't receive Helo's webhooks. For delivery tracking, bounces, and suppression sync, use stechstudio/laravel-postmaster.
• Use outside Laravel. The package needs Laravel.

Live check

scripts/live-check.php sends one email through a real Helo account and lists the first page of suppressions. CI never runs it.

HELO_API_KEY=... HELO_CHANNEL_ID=... HELO_FROM=you@your-domain HELO_TO=you@example.com \
  php scripts/live-check.php

License

MIT. See LICENSE.md.