Deliverability basics

Deliverability is whether your email reaches the inbox at all. Pombo handles the infrastructure; the rest is about how you send.

The foundations

• Authenticate your domain. DKIM, SPF, and DMARC, all passing. Pombo won't send without it. See verify your sending domain, and check what the world sees with the free email authentication checker.
• Use a dedicated sending subdomain, not your root domain, so your marketing reputation stays separate from the rest of your email.
• Warm up gradually. A brand-new domain sending 50,000 emails on day one looks exactly like a spammer. Ramp volume over the first few weeks.

What hurts your reputation

• Emailing people who didn't opt in. The fastest way to get filtered. Buying or scraping lists is the classic version.
• High bounce rates. Mailbox providers read a rising bounce rate as "this sender doesn't maintain their list." Pombo suppresses hard bounces automatically, but importing stale lists still hurts.
• Spam complaints. Even a small percentage of recipients hitting "report spam" moves you toward the spam folder for everyone. Make unsubscribing obvious and easy so people do that instead.
• Sending to people who never engage. Providers weigh engagement. A segment that hasn't opened anything in a year is dragging down every send. Suppress or win them back, don't keep mailing them.

What helps

• Consistent volume and cadence rather than big irregular blasts.
• Real content people asked for.
• Prompt list hygiene: let unsubscribes and bounces do their job, and don't re-import addresses that opted out. See unsubscribes and suppression.

Reports

The DMARC record Pombo suggests sends aggregate reports to dmarc@ your sending domain. Create that mailbox, or point the rua address at a report-reading service, so failures show up rather than passing silently.