Top 10 Subject Line Words That Get Opens

Email list manager provider MailerMailer released its bi-annual Email Marketing Metrics Report (pdf) recently. The report revealed what the company claims to be the most popular words used in subject lines, with regards to attracting readers to open the message.

According to MailerMailer’s report, the top ten words are:

1. news
2. party
3. newsletter
4. free
5. night
6. sale
7. com
8. update
9. holiday
10. week

I would say that the use of any one or combination of these words is not guaranteed to bring you open-rate success, but it is interesting to note which words are commonly used in successful subject lines. I believe the subject line as a whole needs to be enticing, but if these words can enhance a good subject line, perhaps they are at least worth testing (when they fit). Here’s a word cloud from MailerMailer showing these top words and others:

The following graphs from the report indicate that subject line length can have quite an effect:

Subject line Length

Personalized messages seem to do pretty well too:

Personalization - clicks

"The key to leading winning campaigns in the midst of a recession is to move with the ebb and flow of changing subscriber preferences," says MailerMailer CEO Raj Khera.

MailerMailer says that emails are being opened sooner these days. 32.6% of all opens occur within the first two hours compared to 29.6% six months earlier. Click rates went up by .08% in the second half of 2008.

The company also says that email deliverability has been on the rise, with more email reaching recipients’ inboxes. According to the report, religious/spiritual emails get the highest open and click rates.

What do you think about the top ten words? Do you use any of them frequently in your subject lines? If so, do they bring you good results? Tell us about it.

There are 14 Comments. Add Yours.

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Raj Khera
July 6, 2009 at 3:04 pm

Chris, thanks for the post about our email metrics report today. Your readers might also be interested in seeing the word cloud that shows the top subject line words (more than the top 10):

http://www.mailermailer.com/metrics.rwp

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  Chris Crum
  July 6, 2009 at 3:19 pm
  
  Thanks Raj. I might as well embed it.
  
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Ryan
July 6, 2009 at 6:40 pm

Hey, thanks for publishing this.

I can’t figure out how message personalisation would affect the open rate, given this detail is only visible after the email is opened?

Unless message personalisation actually encourages the recipient to display images in the email, allowing the open to be tracked?

Cheers
Ryan

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Roshan Joshi
July 7, 2009 at 1:05 am

I think Hi, Re: & FW: are also quite popular.

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Helen Overland
July 7, 2009 at 10:35 am

Just received this email in my inbox:

Free News Update – Holiday Week Night Party Sale Newsletter at example.com!

All joking aside though, and hoping I don’t receive the above email, this is some great information – thanks for posting.

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  Chris Crum
  July 7, 2009 at 10:46 am
  
  I would totally open that email
  
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Diamonds
July 7, 2009 at 12:48 pm

surprised that “free” is up there, i mean how gullible can you get.

- Like (0) Dislike (0)
  Chris Crum
  July 7, 2009 at 1:17 pm
  
  I’m not surprised by this word. People love free stuff. While it has no doubt been abused, there are still plenty of legitimate campaigns that do offer something for free.
  
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Kevin Webb
July 7, 2009 at 2:24 pm

Some of these words go away once you put them against the tough spam filters. The word “free” is one of them for sure. It is very hard to get a high rate of successful emails to an inbox with the word “free” in the subject line. Even if it does make it through, many people automatically disregard it as spam.

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  Adrian Jock
  July 11, 2009 at 12:27 am
  
  1) MailerMailer is a reputable email marketing company and they know what they say …
  
  2) It is NOT true that the word free is penalized by spam filters. This is a myth! Only some COMBINATIONS of words that contain the word free (and weird – spammy spellings like F.R.R.E.) are penalized by spam filters. That’s a big difference.
  
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Edwin
July 7, 2009 at 10:24 pm

Thanks for the post.
How did ‘night’ get in the top ten?
I would think ‘win’ being ranked quite highly

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primemethods
November 30, 2010 at 9:11 am

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wedding dresses
February 16, 2011 at 4:40 am

Essentially if you

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Dvir Weininger
June 7, 2012 at 12:51 am

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