Two Types of Email
Not all emails are the same. The distinction matters for deliverability, compliance, and how you should send them.
Transactional Emails
These are triggered by a user action. They are expected and time-sensitive.
Examples:
- Password reset links
- Order confirmations
- Account verification
- Payment receipts
- Shipping notifications
- Security alerts
Key characteristics:
- Sent to one person at a time
- Triggered by user behavior
- High open rates (because the user is expecting them)
- Should be sent immediately
- Not subject to unsubscribe requirements (they are not marketing)
Marketing Emails
These are sent to promote products, share content, or drive engagement.
Examples:
- Newsletters
- Product announcements
- Promotional offers
- Re-engagement campaigns
- Onboarding sequences
Key characteristics:
- Sent to many people at once
- Initiated by the sender, not the user
- Must include an unsubscribe link (CAN-SPAM)
- Can be batched and scheduled
- Lower open rates than transactional
Why Separate Them?
Many companies send both types through the same service. This is a mistake.
If your marketing emails get spam complaints, it hurts the deliverability of your transactional emails too. A user missing a password reset because your last promotional campaign got flagged is a serious problem.
Best practice: Use separate sending domains or at minimum separate IP addresses for transactional and marketing emails.
What SMTPfast Is Built For
SMTPfast is designed for transactional emails. Fast delivery, high deliverability, and simple API integration. Every email is sent immediately through a dedicated queue, not batched with marketing campaigns.
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