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Everything you think you know about subject lines is probably wrong

My wife called me recently to ask my professional advice on subject lines. She manages a small email newsletter and uses the broadcast functionality within her web hosting platform (yes, ideally she would be using dotmailer but that is a conversation for another time).

As she typed in her subject line for her next newsletter, a tip popped up that suggested she use all lower case to help with deliverability. This “tip” is problematic for a number of reasons:

  1. My wife is an accomplished writer and has an English degree, so the suggestion of using all lower case was completely offended her.
  2. If using all upper case is the digital equivalent of shouting, using all lower case must be the equivalent of whispering. At the very least it sends a clear message to your recipient of your confidence in the quality of your own content.
  3. It just looks unprofessional and a bit slapdash.
  4. The “tip” was just … WRONG!

Email deliverability and inbox placement is based on the user level ratings across more than 1,000 attributes, so to imply that the case of your subject line will help with deliverability is just nuts. In fact, the biggest driver of inbox placement is user engagement and how likely are your recipients to engage with an all-in-lower-case subject line?

This is the problem with the popular wisdom of email; it is usually wrong. There are no words that you absolutely cannot use in your subject line. Just because your open rate benchmark is 25% does not mean that 75% of your list is unengaged and there is no best or worse day of the week or time of the day to send your email to guarantee an open. What we have here is the equivalent of kids talking about sex on the school playground: there are a few grains of truth and a whole lot of guessing and hearsay.

So what is a marketer to do? First, download our cheat sheet called First Impressions Count: Capture your audience with killer subject lines. After getting some new and fresh ideas from the cheat sheet, I would normally suggest you test these ideas to find out what works best with your audience. I am still going to recommend that but as the third step not the second.

The problem with jumping straight into testing is that more often than not you will get it wrong and it can take a long time to even get near your sweet spot. If only there was a way to start near your sweet spot before you begin testing…

…well there is. There are a number of platforms on the market which use artificial intelligence based on millions of subject lines sent to billions of recipients that will help you find your sweet spot. We partner with a tool called Phrasee and have asked them to join us for a dotlive event on Thursday the 21st at 6pm at our London Bridge office.

So the real answer to the question “what’s a marketer to do” is:

Download our cheat sheet: First Impressions Count: Capture your audience with killer subject lines.

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