Spam Trigger Words to Avoid in Your Next Email Subject Line

Tactics post image
Tactics post image

There are certain words you don’t, can’t, shouldn’t, and mustn’t use within your email subject line if you want to pique people’s interest while avoiding spam blockers. 

It’s one thing if you’re sending a personal email — but if you’re sending mass emails, you’re not going to get very far if 90% of your messages get blocked as spam before they ever reach their intended recipient.

There are so many spam trigger words, someone could write a nice thick book about them. Emails that promise untold riches and exclusive rewards reserved only for a special elite few. Remember that prince from Nigeria?

Let’s get into our list of words to avoid in email subject lines, so you can stay miles away from the spam folder.


What Triggers Spam Filters? Words to Avoid

As with anything in life (except for maybe poker) you want to be open and honest with people. Be direct, be humble, avoid bragging and boasting.

When writing an email subject line, avoid words and phrases like the ones below so you can actually get your message in front of the people you want to reach:

1. Anything to Do With Money

Almost everything that’s associated with a dollar sign — think of your local used car salesman. You not only look sleazy in your email marketing, but the spam filters are sure to pick these up and they’ll never reach their destination.

  • Money back
  • Get paid
  • Cash
  • Dollars
  • Price
  • Big bucks
  • Credit or Debit
  • Profit
  • $$$

2. “Marketing”

Email marketing may be one of the most successful marketing channels out there, but that doesn’t mean email service providers want you clogging up their servers with it. You may be doing marketing when you email clients, but that doesn’t mean you need to remind them you’re doing it. 

Instead, provide actual content in your email that your readers will be interested in engaging with.

3. “Exclusive”

If you have a ‘special offer’ only for a select group of people, use any of the other words to tell people about it, but don’t use these ones.

  • Limited time
  • Get it now
  • Once in a lifetime
  • For new customers only
  • Offer expires
  • Deal ending soon

4. Superlatives

Let your product and your offer do the talking and leave the hard-sell advertising copy to Madison Avenue. Words like INCREDIBLE, and AMAZING smack of desperation and make you look fly-by-night. 

  • Fantastic
  • The best
  • Perfect
  • Unbelievable
  • Wonderful
  • You will not believe your eyes!

5. Days of the Week

This is especially true because of the flood of emails for things like Cyber Monday, Black Friday, Giving Tuesday, and so on. There are significant drops in open rates of emails with day names in the subject line. 

  • Today
  • Soon
  • Last Day
  • Friday before [holiday]

6. Earn

Again, anything that has to do with money, like earning extra income or earning cash, will not only drop the spam hammer, but people are too well-conditioned to believe its promises.

  • Double your income
  • Be your own boss
  • Increase revenue
  • Financial independence
  • Eliminate debt
  • Potential earnings

7. “Free”

This — and “bonus” — may be one of those words that make some people take notice, but many more see it as open-bait.

  • 100% off
  • Allowance
  • Gift included
  • Rebate
  • 0 down

Honorable Mentions

Emojis – Emojis and symbols ($$$) are major spam triggers.

All caps – CALM YOURSELF. Create excitement with your tailored content instead.

Excessive punctuation – It’s a sure way to let your reader know you’re cheap and unprofessional in less than 10 seconds. (Check this out!!!!!!)


Make Email Marketing Work For You

To start, try to avoid sending generic messages to everyone in your database. It can be difficult, especially with limited resources and pressing deadlines. But segmenting your audience, personalizing your messaging, following email subject line best practices, and testing frequency can lead to improved open and click-through rates.

Hopefully, once you start building an email relationship with your recipients, your messages will make it to their inbox. But when you’re starting out with those initial conversations, don’t risk anything. Avoid “spam trigger words” in your email subject lines and keep on the email servers’ good side.