Crafting compelling email subject lines is crucial for engaging your audience and boosting open rates. However, certain words and phrases can trigger spam filters, causing your carefully crafted emails to be sent straight to the junk folder. To enhance deliverability, it’s essential to understand which terms to avoid.

In this guide, we’ll explore why spam filters flag certain words, highlight 100 common spam triggers, and provide tips for crafting subject lines that improve email performance.

Why Do Spam Filters Flag Certain Words?

Email providers like Gmail, Outlook, and Yahoo use advanced filtering systems to detect and block unwanted emails. These filters analyze subject lines, content, formatting, and sending behavior to identify potential issues. Words commonly associated with scams, aggressive sales tactics, or misleading claims can raise red flags, increasing the likelihood that an email will be marked as spam.

By avoiding these terms, marketers can improve deliverability, maintain sender reputation, and enhance overall engagement.

100 Words and Phrases to Avoid that Trigger Spam Filters

1. Financial and Money-Related Terms

• Free money
• Cash bonus
• Get paid
• Make money
• Earn extra cash
• Unlimited income
• Fast cash
• Increase sales
• Financial freedom
• Work from home

2. Urgency and Pressure Words

• Act now
• Urgent
• Limited time
• Don’t miss out
• Hurry
• Final notice
• Once in a lifetime
• Instant access
• Time-sensitive
• Exclusive deal

3. Overpromising and Misleading Claims

• Risk-free
• No hidden fees
• Guaranteed
• 100% free
• Promise you
• No catch
• No obligation
• You have been selected
• Congratulations
• Click below

4. Sales and Discount Phrases

• Lowest price
• Best price
• Sale now
• Discount
• Bargain
• Buy direct
• Order now
• Special promotion
• Save big
• Winner

5. Email and Online Security Triggers

• Password
• Account update
• Confirm your identity
• Access now
• Click here
• Unsubscribe
• This isn’t spam
• Verify your account
• Your bill
• Important information

6. Health and Medical Claims

• Miracle cure
• No side effects
• Weight loss
• Shed pounds
• Anti-aging
• Enhance performance
• Improve your health
• Cure
• Doctor recommended
• Scientifically proven

7. Gambling and Sweepstakes Terms

• Jackpot
• You’re a winner
• Free entry
• Win big
• Lottery
• Scratch and win
• Prize inside
• Casino
• Betting
• Claim your prize

8. Common Phishing and Scam Words

• Urgent response needed
• Confidential
• Sensitive information
• Final warning
• Your account is on hold
• We need your information
• Verify now
• Suspicious activity
• Billing department
• Act immediately

Tips for Writing Effective Subject Lines

Avoiding spam trigger words is just one part of crafting a successful email subject line. Here are some additional best practices:

1. Keep It Concise: Aim for 6-10 words or fewer than 60 characters for improved readability and mobile optimization.
2. Personalize When Possible: Use the recipient’s name or reference past interactions to increase engagement.
3. Create Curiosity Without Clickbait: Instead of “Huge Discount – Act Now,” try “Your Exclusive Offer Inside.”
4. Use A/B Testing: Test different subject lines to see what resonates most with your audience.
5. Focus on Value: Highlight the benefit of opening the email rather than making exaggerated claims.

Steering clear of spam trigger words in your email subject lines can significantly improve deliverability, open rates, and engagement. By using clear, honest, and compelling language, you can ensure your emails reach the right audience and drive meaningful interactions.

Now that you know which words to avoid, it’s time to refine your subject lines and optimize your email marketing campaigns for success!