"Why is my email going to spam?" is one of the most common questions we see from developers. Nine times out of ten, the answer is this: you're sending transactional and marketing email from the same domain (or even the same sending identity), and the marketing mail is dragging your reputation down for everything.

The core distinction

Transactional email is triggered by a user action — a receipt, a password reset, a shipping notification, an OTP. The user expects it and, crucially, engagement rates are high. Marketing email is bulk or campaign-driven — newsletters, promotions, re-engagement flows. Engagement rates are lower and some users will mark it as spam.

ISPs (Gmail, Outlook, Apple Mail) factor engagement signals — opens, clicks, moves to inbox, marks as spam — into domain reputation scores. Low-engagement marketing mail can suppress deliverability for your transactional mail if they share a sending domain.

Separate your sending identities

The fix is straightforward: use different subdomains (and ideally different IP pools) for transactional and marketing sends. In Wasika, you configure this as separate sending identities:

bash 
# Transactional — high reputation, user-triggered
"from": "noreply@mail.yourapp.com"

# Marketing — separate domain, separate reputation
"from": "hello@updates.yourapp.com"

List hygiene and unsubscribes

Hard bounces should be suppressed immediately. Wasika handles this automatically — a 5xx SMTP response adds the address to your suppression list and no future sends will attempt delivery. Soft bounces (mailbox full, temporary failure) are retried with exponential backoff.

Unsubscribes must be honoured within 10 days under CAN-SPAM and immediately under GDPR. Wasika's suppression list is shared across your account — an unsubscribe from a marketing campaign automatically prevents future marketing sends to that address, without any application code.

Authentication: SPF, DKIM, DMARC

If you haven't set up SPF, DKIM, and DMARC on your sending domains, do it today. Gmail and Yahoo now reject unauthenticated bulk mail outright. Wasika's domain setup wizard walks you through all three DNS records and shows you a live DMARC alignment report so you can see what's failing before it affects deliverability.