Back to main menu

Email best practices

100+ email spam words to avoid in your email marketing campaign

While it’s industry folklore that certain words trigger spam filters, there are certain words you’ll want to avoid if you’re looking to improve your overall email deliverability.

Hermes dancing on a laptop next to a mug

PUBLISHED ON

PUBLISHED ON

We’ve all received spam email at some point in our lives. In fact, most of us run into it every day; miracle cures for cancer, pills promising to make our problems disappear and, of course, the classic Nigerian prince who occasionally comes knocking with his financial windfall.

Unfortunately for our Prince, people are becoming increasingly aware of his data-stealing antics so know not to avoid his mail like the plague. The same is true for email service provider (ESP) spam filters, which are better adapted and equipped to recognize phishing emails and boot them into touch.

But what does all this have to do with the words we use in our email marketing campaigns? Good question. There are certain words that when added to subject lines can lead to high complaint rates and low engagement. Both have a negative effect on sender reputation – one of the leading factors behind poor email deliverability.

Clearly this is something as an email sender you’ll want to avoid. So, to help you avoid being thrown in with the spoofers and bad actors of the world, we’re going to share some of those email spam words you’ll want to avoid using in your upcoming campaign.

Busting the myth

Before we get started, it’s important we debunk a common misconception among email marketing professionals – the idea of absolute "email spam trigger words" words is, in fact, false. Let us quickly explain why.

Spam filters look for a combination of tactics used by spammers, with words being just one piece of the puzzle. There are many factors behind the triggering of spam filters, such as:

  • Sender reputation: Unknown senders with no domain reputation are more likely to be flagged.

  • Poor design: Emails with excessive ALL CAPS, unusual fonts, or bad grammar raise red flags.

  • Missing information: Lack of a clear email header, company information, or unsubscribe option can be suspicious.

  • Deceptive practices: Misleading subject lines, hidden URLs, or impersonating legitimate companies (email spoofing) are all red flags.

So, it's not just words, but how they're used in conjunction with other techniques that trigger spam filters.Also,context matters. Words like "free" or "urgent" can be legitimate in certain contexts (e.g., a sales email offering a free trial or an important notification). Spam filters rely on analyzing the entire email for red flags, not just isolated words. And don’t forget, it’s not just the spam filters. Email recipients are also triggered by certain keywords and if they suspect something phishy is going on, they’ll soon mark it as spam.

That said, there are still words and phrases commonly associated with spam that can increase your chances of landing in the spam folder. It's wise to be mindful of these and use them cautiously.

“Early spam filters were focused more on words, punctuation and the content of your email campaign. I’m not saying that’s not relevant today – because it is – but much more focus is being put on reputation. How you are as a sender is what’s going to determine where your messages go.”

Nick Schafer, Senior Manager of Delivery and Compliance at Sinch Mailgun

Email spam words

So, what exactly are email spam words? Well, in most cases, they’re words designed to create a sense of urgency or pressure to act now. They tend to make exaggerated claims, suspicious financial promises, or use shady, promotional tactics to lure recipients in. We’ve categorized some of the most common email spam words and phrases you’ll want to be aware of before crafting your next campaign.

False urgency and scarcity

  1. Act now

  2. Limited time only!

  3. Don't miss out

  4. Expiring soon

  5. Last chance

  6. Hurry

  7. While supplies last!

  8. Ticking clock...

  9. Don't wait!

  10. This offer won't last

  11. Limited availability

  12. Selling fast

  13. Only a few left

  14. Exclusive offer

  15. Rare opportunity

  16. Don't be left behind

  17. This won't be repeated

  18. Once-in-a-lifetime deal!

  19. Supplies are running low

  20. Quantities limited

Banking, finance, and the lottery

  1. Urgent action required

  2. Account verification

  3. Suspicious activity

  4. Unclaimed funds

  5. Limited time offer

  6. Consolidate your debt

  7. Pre-approved loan

  8. Easy money

  9. Get rich quick

  10. Double your money

  11. You've won!

  12. Millions waiting

  13. Unclaimed prize

  14. Lucky numbers drawn

  15. Final chance!

  16. Claim your prize!

  17. Life-changing opportunity

  18. Congratulations!

  19. Exclusive offer

  20. Free ticket

Marketing and sales promotions

  1. Free

  2. Discount

  3. Sale (or variations like "Mega Sale")

  4. Limited

  5. Act

  6. Don't miss out

  7. Exclusive

  8. Best price

  9. Guaranteed (especially with unrealistic claims)

  10. Winner

  11. Bonus

  12. Clearance

  13. No obligation

  14. Risk-free

  15. Get started now

  16. Hurry!

  17. All-new

  18. Special offer

  19. Click here (repeated excessively)

  20. Unbelievable results

Sex, drugs, and rock n’ roll

  1. Adult

  2. Singles

  3. Enhancement

  4. Uncensored

  5. Discreet

  6. Chat

  7. Flirt

  8. Meet

  9. Lonely

  10. Seduction

  11. Enhancement

  12. High

  13. Prescription

  14. Weight Loss

  15. Pain Relief

  16. Euphoria

  17. Viagra

  18. Party

  19. Molly

  20. Ecstasy

Exaggerated claims and hype

  1. Miracle

  2. Breakthrough

  3. Secret

  4. Scientifically proven

  5. Doctors recommend

  6. Guaranteed

  7. Hidden

  8. Once in a lifetime

  9. Risk-Free:

  10. Clinically proven

  11. New and improved

  12. All-natural

  13. Double your money back

  14. Stop aging now!

  15. Lose weight

  16. Without diet or exercise!

  17. The secret to wealth

  18. Work from home and make thousands!

  19. Look 10 years younger

  20. This one trick!

Again, we want to make it clear here that context is King. Using these keywords in isolated incidents is not going to automatically land you in the spam folder. Internet service providers (ISPs) use various checks when deciding to flag an email as spam, or not.

Watch our recent Email Academy webinar series episode where the team give tips and advice on how you can maximize the chances of your campaigns landing in subscribers’ inboxes.

How to avoid the spam folder

So, we’ve established that email spam words are just a small part of what triggers filters. What about some of the other factors? If you’re ready to take your email deliverability up a notch and want to really avoid those spam filters, you’ll need to start thinking about some of the following areas:

Maintain a healthy email list

Sometimes it’s possible to have too much of a good thing, which is certainly true for your email lists. While it might be nice to sit back and marvel at impressive subscriber figures, it’s far more important to monitor engagement. Why? Because if people aren't interested in your content and mark your emails as spam, it hurts your sender reputation. Therefore, a little email list cleaning is sometimes needed.

A clean list with interested subscribers means your emails are more likely to be opened and interacted with. This positive engagement signals to email providers that you're a legitimate sender (and not a bad actor). A healthy list also reduces bounces, which happen when emails can't be delivered due to invalid addresses. Remember, high bounce rates can also signal to ISPs that you’re not sending relevant content and potentially move your campaigns to the spam folder.

Double opt-in

It seems counterintuitive to add a step to the onboarding process, right? Marketing lore dictates that the process be as smooth and hassle-free as possible. So why would we ask new subscribers to complete an additional step before they can receive our campaigns?

By asking subscribers to verify their email through a double opt-in process, you’ve already scored your first interaction. This is a positive signal for ESPs and a great way to boost your sender reputation. Plus, when subscribers engage with your double opt-in email, they are essentially re-confirming their interest in receiving your newsletter. This means it’s extremely unlikely that they’ll then classify your emails as spam further down the road.

So, while it might appear counterintuitive to have fewer total subscribers in your email list, your engagement levels will be higher which is a far more important signal to ESPs trying to keep you out of the spam folder.

Pro tip: For a detailed walkthrough on how to set up double opt-in forms through your Sinch Mailjet account, we’ve documented the step-by-step process here for you to follow.

Use a custom domain

A custom sending domain is essentially your own personalized address used for sending emails. Typically, as a professional or SMB owner you’ll want a custom sending domain that matches your business website and aligns with your brand.

Why is this important? Well, once you’ve got a custom email address you’ll be able to set up DKIM, SPF, and DMARC which will allow for email authentication from recipient servers.

This is great news not only for your domain reputation, but also makes it much harder for bad actors to spoof your brand and protects your subscribers from phishing attacks.

Watch our recent Email Academy webinar series episode where the team runs through how to set up your own custom domain

Honor the unsubscribe button

It’s never a good idea to bury your unsubscribe link somewhere where people can’t find it, or make it difficult, time-consuming or confusing to do so (especially considering Google and Yahoo have now made it a mandatory requirement for bulk senders).

It’s going to result in a negative experience for subscribers, and if they can’t easily locate it, they may just mark you as spam. Not something we want when trying to avoid the spam folder.

So, while it might seem counterintuitive to offer subscribers as an easy way out, it’s extremely important you do so. If you’re providing subscribers with high-quality, relevant content) then this shouldn’t be a problem!

Mailjet’s unsubscribe link in email footer

Notice the one-click unsubscribe button at the bottom of the Sinch Mailjet email marketing newsletter

Start sending emails to the inbox with Sinch Mailjet

Understanding the words that trigger spam filters is crucial for your effective email marketing. By carefully selecting your language and avoiding these red flags, you can significantly increase the chances of your emails landing in the inbox rather than the spam folder.

Remember though, email spam words are only part of the puzzle. Adhering to email deliverability best practices is not just about avoiding spam filters; it's about building trust with your audience. Sending relevant, valuable content and respecting recipients' privacy, you'll improve your email reputation and ensure that your messages reach the right people. A strong sender reputation is the cornerstone of successful email marketing!

Get world class email deliverability support

Maximize the success of your email campaigns and reduce the amount of content landing in your recipient’s spam folder with our Deliverability Services offering, where a dedicated account manager will be on hand to help you every step of the way.

Popular posts

Hermes rides a firework next to a Goddess in front of a night sky with more fireworks

Email best practices

6 min

Top email marketing trends for 2022

Read More

Hermes on a moped delivering mail to a mailbox

Email best practices

8 min

Reducing email’s carbon footprint

Read More

Mother's day gift for Hera

Marketing

15 min

Marketing calendar 2025: Dates you shouldn’t miss this year

Read More

It's never been easier to build connected experiences. Start sending with Mailjet today.Get started on your path
CTA icon