The words that trigger email spam filters

Triggering spam filters with the words in your emails can be devastating for your marketing. It lowers your open rates and could have serious effects on your conversions. If you want to make sure your emails are landing in inboxes rather than spam boxes, be careful these words that could put filters into overload.

Some words have to be used. There are few marketing businesses that get by without ever writing “click here”, but it’s all about where and when you say it. These are the phrases that may be a necessity to your email marketing, but should be kept out of the first paragraph, and most definitely the subject line.

Be careful when using...


“As seen on”


“Click here”


“Gift certificate”


“Orders shipped by”


“The following form”

“Work from home”


Then there are the words that you need to keep well away from your emails. These are the ones likely to send your emails straight to spam boxes, never to even be seen, let alone opened. If at all possible, do not let these phrases end up in your email marketing.

At all costs, avoid...

“100% free”

“Can’t live without”

“Complete for your business”

“Increase your sales”

“Incredible deal”

“Lowest price”

“No strings attached”

“Special promotion”

“This isn’t spam”

“Visit our website”

“You’re a winner”


Of course, it’s not a known science. Every spam filter is different and one email will set the alarms blaring on Gmail, but be happily passed through by Hotmail. These words are a guide and have hopefully flagged up some phrases you didn’t think about, but it’s all about experimenting and working out what emails will find their way into your fans’ inboxes.

For another great way to improve your email marketing, make sure you check out our guide to A/B testing and find out what it can do for your business.


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