Do “spammy” words affect cold deliverability?
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If you've ever Googled "words to avoid in cold email," you've probably landed on a list with entries like "FREE," "highly likely," "ACT NOW," and "CLICK HERE." Those lists make it sound like spam filters are just ctrl+F searching your drafts. They're not.
Modern spam filters use machine learning. They don't flag individual words in isolation. They look at patterns across thousands of signals at once. A word like "free" in a cold outreach email from a well-authenticated domain with solid engagement history is not going to sink you. That same word in a blast from a cold IP with no SPF or DKIM, sent to a purchased list? Different story entirely.
What actually drives filtering decisions for cold email:
- Sender reputation is the biggest factor. How your domain and IP have behaved historically matters far more than any word choice. If your cold outreach is generating complaints or hitting spam traps, that damages your reputation fast.
- Authentication is table stakes. If you don't have SPF, DKIM, and DMARC in place, filters treat you with suspicion before they've even read your subject line.
- Engagement signals are what filters trust. Replies, opens, and low complaint rates tell filters your emails are welcome. Cold outreach that gets ignored at scale trains filters to keep routing you to spam.
- Template patterns can hurt you. Sending hundreds of near-identical emails triggers pattern recognition. It's not the words, it's the sameness. Mix up your copy across sequences.
That said, certain phrases are worth avoiding. Not because of magic blacklists, but because they signal low-quality intent. "highly likely ROI," "act now before this expires," "re:" in a subject line when it's not actually a reply, and "fwd:" when nothing was forwarded. These aren't filter triggers by themselves. They just read as manipulative, and that erodes trust with the human on the other end, which then erodes your engagement signals over time.
Write like a person reaching out to another person. That's it. If you'd feel awkward saying something out loud in a first meeting, don't put it in a cold email either.
The bigger cold email risks aren't vocabulary. They're technical gaps (missing authentication), list quality issues (stale or bought contacts), and volume mistakes (ramping too fast on a new domain). Fix those first. The word list anxiety can wait.
If you want to check whether your domain's authentication is set up correctly before sending anything cold, our free SPF checker is a good starting point. And if your cold email templates are already showing deliverability problems, that's a different conversation worth having.
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