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What makes a subject line work? Episode 3 – Individual Word Choice

Email subject line performance can be impacted by many, many things.


That’s why finding the perfect subject line for a brand’s email marketing campaign is so darned exhilarating.

The quality of an email subject line can make or break any email marketing campaign, and better subject lines are the best way to help brands make more money through the lucrative email channel.

Over our years experimenting with email subject lines with the help of our awesome AI technology, we’ve found that there are a few key factors in how an email subject line is constructed that directly impact that subject line’s performance.

They are:

  • Sentiment
  • Length
  • Phreshness
  • Word choice
  • Language sophistication
  • Scansion (Our CCO’s favourite)

We’ve decided to share what we’ve learned about these key subject line elements with our email marketing compatriots over 4 blog posts.

This week, we look at individual word choice…



What is individual word choice?

When constructing any sentence or message, there are approximately 171,476 words in common use in the English language to choose from. Many of these words have extremely similar – if not identical – meanings to others.

In other words (see what we did there?), there are millions (trillions, even) of word combinations one could potentially use to convey any single message or sentiment in even the briefest of sentences.

Which combination of individual words you use to build an email subject line can have a big impact on how that subject line is received and interpreted by your audience.


Why does it matter?

With that many ways to say something, what are the odds that you’ll choose the optimal combination of individual words when constructing a subject line?

Pretty slim, if you really think about it.

Which is a shame, because every less-than-optimal subject line you send represents lost revenue.

Different audiences respond to different individual word choices in different ways, and this important fact should be a key driver in developing any sound email subject line strategy.

The only way to stay ahead of the curve is with regular, ongoing split-testing.


How can brands put this information to use?

Identifying which individual words engage an audience most effectively is an excellent first step toward better email subject line performance. Split-testing different words (and combinations of words) on your audience regularly – with a solid plan in place to learn from the results of your tests – will give you a good indication which individual words are most likely to work for your brand on any given send.

Always keep in mind that the individual word choices your brand makes are a key aspect of your brand’s unique tone of voice. Maintaining consistency in your language is key, and matters just as much in your email subject lines as it does anywhere. Every touchpoint is a branded moment, and protecting consumer perceptions of your brand should always take precedence.

Luckily, with enough testing data to draw from, striking the right balance between high performing individual words and your unique brand voice is entirely possible – as long as you are willing to invest the time and effort necessary to find the right balance for your brand.

If you keep testing, and keep high-performing word choices front of mind when building your brand’s email subject lines, you’ll soon see your email marketing ROI grow.Better still, Phrasee’s AI language generation and split testing technology can do this all for you, simplify the process, and help your brand make more money sooner, rather than later.  Book a demo to find out how!

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