SparkPost

SparkPost (MessageBird)

High-volume transactional email infrastructure. 500 emails/month free; pay-as-you-go after that.

Easy~5 minAPI

Prerequisites

• A SparkPost account. Free tier: 500/month.
• A verified sending domain.

Step-by-step

Verify your domain

SparkPost → Configuration → Sending Domains → Add Domain. Enter your domain.

Add the SPF, DKIM, and (optional) DMARC records SparkPost displays at your DNS provider. Click Test to verify.

Generate an API key

SparkPost → Configuration → API Keys → New API Key.

• Name: SendGrail
• API Permissions: Send via SMTP (the only scope you need for SMTP/API sends)

Click Create API Key. Copy the key.

Add the connection in SendGrail

WordPress admin → SendGrail → Connections → Add Connection → pick SparkPost.

Fill in:

• Connection Name: SparkPost
• From Email: your verified domain address
• From Name: display name
• API Key: paste from step 2

Click Save.

Test

SendGrail → Test Email → pick SparkPost → send.

Troubleshooting

Permission denied

API key lacks Send via SMTP permission. Edit the key in SparkPost dashboard or generate a new one with the right scope.

From address rejected

The From Email domain isn't verified in SparkPost. Verify it in step 1 above.

Invalid_credentials

Wrong API key. Regenerate in SparkPost → Configuration → API Keys.

What's next

• Email Routing — route high-volume transactional through SparkPost.
• Failure Alerts — get notified on SparkPost rejections.