The subject line is such a small simple cog in the giant machine of email marketing, it's often overlooked by business owners. When even the smallest cogs break down, whole machines can cease to work. Below are some tips for ensuring you don't break your email marketing machine by making the subject line strong as possible.
1. Don't Put the Main Before the Entree
Email subject lines are a teaser and should be treated as such. It's the entree and the content of the email is the main (or appetizer and entree for the American crowd). You don't want to get to the main point of your email before they even look at it. People often see their spam box littered with subject lines that try to sell a whole offer in the subject line. Those will rarely be opened and even more rarely convert into sales. This leads me to the next point.
2. Keep the Subject Line Short
This is for two reasons. One, so you don't try to fit an entire sales pitch into one line. Two, most of that subject line will get cut off due to people reading emails on an increasingly smaller screen. 53% of all email opened in Q3 of 2014 occurred on a mobile phone or tablet. – Experian “Quarterly email benchmark report” (Q3 2014). With less and less space for subject line text, it's optimal to keep subject lines between 4-7 words with less than 50 characters as anything more is likely to get cut-off. It's difficult to encapsulate a meaningful message into 4-7 words, so think of it as more of an invitation than a sales pitch.
3. Be Personable and Simple
With the idea of keeping subject lines as an invitation. Keep your email subject lines simple and personable. Speak to the receiving end of this email as a person, not as a possible conversion or another metric to be measured. Knowing your audience is essential for this tip. There's a vast difference between what's personable for a CEO of a fortune 500 company than a small business owner who runs a hammock business on his computer in Thailand. Studies have shown personalized subject lines are 22.2% more likely to be opened (Adestra July 2012 Report). Simply using a recipient's name in an email can have a large effect getting your emails read and creating a relationship with your audience. In keeping it simple, don't go overboard with ALL CAPS or using obnoxious marketing fodder like FREE! or HUGE DISCOUNT!
4. Tell, Don't Sell
Email subject lines have a lot in-common with the overlying theme of inbound marketing. It's best to provide value for your email readers. Thus, it's best to simply tell what's inside of your email instead of prescribe to any gimmicks. Even if you use some absolutely crazy offer to get your targeted audience to open your email, when they realize the email contains zero substance inside, you'll soon find your message with a first class ticket to spam land.
5. Test Subject Lines Beyond the Click-Through Rate!
Testing is a key in marketing any business. Using a formula that's successful in one company may not translate to success for another company. It's always best to record and test your results in analytics based on your most pertinent business metrics. When testing don't simply rely on open or click-through rates and call it a day. Define your business goals within the email and base your testing on conversions, engagement, subscriptions, whatever metric you choose, but go beyond the click-through rate. These can all be set up with relative ease in Google Analytics and let you to visualize the ROI your email marketing efforts are contributing. This can help you optimize your subject lines and emails to better achieve business goals.