SMTP, deliverability, and why your emails land in spam

Deliverability has a reputation for being dark magic. It isn't. It's a trust system, and once you see it that way, the rules stop feeling arbitrary. Mailbox providers - Gmail, Outlook, the rest - are constantly asking one question about you: does this sender seem like a real person people want to hear from, or a machine people want to escape?

Everything below is just ways of answering that question with a confident yes.

Send from your own, properly set-up domain

This is the foundation, and it's why Leadiy sends campaigns through your connected email over SMTP rather than some shared blast server. Mail from your real address, authenticated with the standard records your provider supports, tells the receiving server you're accountable. Anonymous mail from a shared IP is the opposite signal.

• Use an app password and the correct host and port for your provider - the setup screen fills these in for you.
• Send yourself a test before every campaign. It catches the boring problems that quietly tank a send.
• Warm up gradually. A brand-new address that suddenly emails 2,000 strangers looks exactly like a spammer, because that's what spammers do.

Content still matters, just not how you think

You won't get filtered for saying "free" once. You'll get filtered for looking like bulk mail: image-only emails, a dozen links, shouty formatting, and - the big one - low engagement. If nobody opens or replies, providers learn your mail is ignorable and start hiding it. The fix is the same as good outreach generally: relevant, personal, wanted.

The unsexy checklist

Keep your list clean so you're not hammering dead addresses. Include a genuine unsubscribe and a physical address - it's the law in most places and, conveniently, also a trust signal. Don't buy scraped lists; the bounces alone will torch your reputation in a week.

None of this is glamorous, and that's the point. Deliverability rewards the sender who behaves like a considerate human at scale. Do the boring things and the inbox opens up. Skip them and no clever subject line will save you.