Do “spammy” words really matter?

You've probably heard that writing "FREE!!!" in all caps will instantly torpedo your email into the junk folder. That was true once. Today, it's a much more complicated picture.

Modern spam filters don't just scan for suspicious words. They look at the full picture of who you are as a sender. Gmail and Outlook are running machine learning models that weigh your sender reputation, your authentication setup, and how your subscribers have engaged with you over time. A word like "free" is one tiny signal in a system processing hundreds of them.

So do spammy words still matter at all? A little. They're not the deciding factor on their own, but they can tip the scales if everything else is already borderline. Think of it this way: if your reputation is solid, your authentication is clean, and your subscribers actually open your emails, you can write "free offer inside" without losing sleep. But if your reputation is shaky, adding a pile of ALL CAPS urgency phrases into a poorly structured email with low engagement isn't going to help.

The real shift in strategy isn't about avoiding specific words. It's about building the conditions where your words don't matter much at all. That means:

• Authenticating your domain with SPF, DKIM, and DMARC so mailbox providers trust who you are
• Sending to people who genuinely want your emails (permission matters more than phrasing)
• Keeping your list clean so you're not mailing cold addresses or spam traps
• Writing emails people actually open, click, or reply to (engagement is a signal filters love)

The practical advice is to write naturally. If "free" describes your offer accurately, use it. If your business legitimately discusses pharmaceuticals, don't tie yourself in knots trying to avoid the topic. Filters have gotten good enough to understand context. What they haven't gotten better at is forgiving senders with a poor reputation who pile on sketchy signals all at once.

Write for the human. Make sure your technical foundation is solid. That's the actual lever here. (Of course, that's easier said than done, which is why so many senders still obsess over word choice instead.)

If you want to check your authentication setup first, our free SPF checker is a good place to start. Or if something's actively broken, reach out via our SOS hotline and we'll take a look.