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What My Own Results Have Taught Me About Email Subject Lines

Back in December, I created and shared a schedule to help you stay on top of your marketing. One of the tasks was to look at your email subject lines every year, so in January, I did. 


While I can’t say I was shocked at what I learned, there were some surprises. As I’ve been urging you to do for years, I A/B test my subject lines. They are proven to boost open and click rates. It’s been true for me and for every one of our clients (except one! Reasons why are still a mystery). 


I use Mailchimp, and I started digging around on their site to understand how a winning subject line is determined. Instead, I found something interesting that I did not know: when you have a small list, send the A/B test to all recipients rather than splitting the test among two groups. 


(Mailchimp doesn’t define a small list, but I think a list with fewer than 1,000 people on it can be considered small. And by the way, small isn’t bad. Quality – in this case, the number of people who engage with your emails – always trumps quantity.)


What my own results have taught me about email subject lines


Questions don’t always win


Asking questions generally catch people’s attention. If it’s interesting or relevant, they’ll naturally want to know the answer. For this reason, I use questions in my email subject lines a lot.


But they don’t always win in an A/B test.


In February 2021 and July 2021, the subject lines that included a question did not win:


February Winner: This is the content that drives social media engagement

February Loser: Want to increase social media engagement? Here’s what to share


July Winner: You should be writing long blog posts – here’s why

July Loser: Shouldn’t you be writing long blog posts? (Hint: Yes)


But in August 2021 and November 2021, they did win:


August Winner: What kind of content will people pay for?

August Loser: This is the content people will pay for


November Winner: Do you randomly add people to your email list? Tsk-tsk

November Loser: Don’t build your email marketing list by doing this


I’ll let you know what the winners and losers have in common below.


Shorter is better


When you A/B test your email subject lines, Mailchimp doesn’t warn you if you exceed nine words. If you’re not A/B testing, Mailchimp will absolutely call you out and remind you to write shorter email subject lines.


When it comes to content, shorter is better, period. Of the winning subject lines from 2021, eight were less than nine words. The other four were 10 words. 


The reasons to stick with nine words or less are twofold:


1 – People skim their email subject lines; make it easy for them to get the gist of your email.

2 – When reading email on their mobile devices, only shorter subject lines appear in full.


One of my shortest email subject lines from 2021 had the highest open rate of the year at 43.8%: What kind of content will people pay for? 


Granted, that subject line also had to do with making money. Interestingly, the loser email it went up against had a huge click-through rate at 9.3%. 


Straightforward is better, too


One clear takeaway from my winning subject lines in 2021 is that clear and straightforward subject lines do better. This I know – it’s one of the hallmarks of my copywriting. But in trying to write creative and interesting variations of subject lines, I sometimes go too far.


February’s winner and loser are a great example:


February Winner: This is the content that drives social media engagement

February Loser: Want to increase social media engagement? Here’s what to share


Looking back on it, I just want to slap myself with a wet noodle. How did I let the loser subject line get so wordy?


I repeated this mistake in June and again in October:


June Winner: Your marketing is working when total strangers are your prospects

June Loser: Are your sales prospects strangers? Congrats! Your marketing is working


October Winner: Should you use memes for marketing?

October Loser: Want to boost audience engagement? Use memes for marketing


People love to learn from personal experiences


Since the start of the pandemic, I have shifted my blogging to be much more personal. I write a lot more about my own marketing experiences and the things I’m curious about. In the past, I wrote more how-to, educational posts. There’s still a place for those, but I’ve found that my new approach has resonated big time. 


Because the titles of my blog posts turn into my email subject lines, I can see a clear connection between the more personal content and open rates.


In April 2021, I wrote about whether weekly emails or monthly newsletters had better engagement. Two of my friends and colleagues had started sending out weekly emails, and I was genuinely curious about what worked best. The winning subject line had a 35.8% open rate and a 6% click-through rate.


In December 2021, I wrote about the marketing schedule I created for myself (which I mentioned above). That had a 38.3% open rate and a 5.5% click-through rate.


Other ways to improve your subject lines


If you look at my past email subject lines above, you’ll notice they all have one thing in common: They are very specific about what information you’ll find in the email. Avoid generic or vague subject lines. 


Instead of: Shop our sale!

Try: Save up to 60% on all spring merchandise!


If you use Mailchimp for email marketing, take advantage of their subject line helper. It tells you if your subject line is too long, contains too many emojis, or goes against another best practice. 


Speaking of emojis, treat them like punctuation and don’t go overboard. One exclamation point is plenty. So is one heart, rabbit, or city building. (I don’t use emojis in my email subject lines, by the way. If they feel right to you and your brand, go for it.)  


Are your subject lines working for you?


If your open and click-through rates are dismal, let’s set up a one-hour consultation. We’ll review your subject lines and discuss ways to improve them. Just shoot me a note here and we’ll get a date on the calendar. 


  • Greg Voornas
    Posted at 17:13h, 09 June Reply

    Great insights, and very practical advice – thanks!

  • Monika Jansen
    Posted at 10:34h, 13 June Reply

    Thanks Greg!

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