Hey, picture this:
You drafted the perfect email for… well… your boss! No typos, nothing wrong, all info! You click send and then you wait, wait, WAIT and you call him. He doesn’t see it in the Inbox folder. You say the black words: check the spam folder. And then he says “Oh now I see it“… dissepiment, right? But why?
For the not so tehcies:
Think of email like showing up to someone's door. If you show up in a sketchy car, from a neighborhood with a bad reputation, with no ID, saying "FREE OFFER CLICK HERE" — yeah, you're not getting in. The spam filter is basically a bouncer, and it's judging you before you even knock.
The most common reasons your email gets flagged:
The service you're sending from has a bad reputation (cheap or poorly set up)
Your subject line or content uses words that scream "scam" — ALL CAPS, too many exclamation marks, words like FREE or URGENT
The recipient never interacts with your emails, so over time the system learns to push you aside
You never set up the basic "ID cards" that prove you are who you say you are
The fix isn't complicated, it's just a bit of setup. Once it's done right, your emails land where they should. No phone calls required.
For the techies:
Your email hits a receiving MTA and gets scored before it goes to an inbox. Here is what's working against you:
Reputation problems -- Your sending IP or domain is on a blacklist, or you're on a shared IP with dirty neighbors. Check MXToolbox. If you're on a shared host with a bad reputation and haven't warmed up a dedicated IP, yeah…
Authentication gaps -- No/Wrong SPF, misaligned/no DKIM, or a missing/wrong DMARC policy. Receiving servers can't verify your identity, so they don't trust you.
Content scoring — Spam filters score your content. Heavy HTML, image-to-text ratio off, URL shorteners, links to low-reputation domains, spam trigger words in subject or body all add up. Test your email with tools like Mail Tester first, unless it has confidential information!
Engagement signals -- Gmail and others factor in historical engagement. Low open rates, high spam complaints, or sending to dead addresses tanks your sender reputation over time. Clean your lists. Use sunset policies. Monitor your postmaster data.
Infrastructure misconfiguration -- PTR record doesn't match your HELO hostname, no BIMI, MTA-STS not enforced, or you're routing outbound through a misconfigured relay. These are smaller signals individually, but they stack.