5 Email Subject Line Best Practices

    by Mark Kilens


    April 25, 2011 at 12:52 PM

    Email subject lines are the most important thing to get right when doing email marketing. A bad subject line could get your emails caught by spam filters, not opened, or get people to unsubscribe from your list.

    An email subject line should be like a call to action. The action you want someone to take is to not only open the email, but to do something in the email. During the upcoming email marketing Content Camp we will explain why every email must have a call to action and a specific goal.

    email subject line best practices

    1.  Action-oriented

    Email subject lines must convey action and should start with an action verb such as learn, download, or sign up. Subject lines should speak directly to the recipient in an active tone, which will result in getting them to notice the email. Having an action-oriented subject line makes the email standout from the other emails in their inbox.

    Another tip is to use one keyword in the subject line that people will recognize. The keyword should be a non-branded keyword like “blogging best practices.”  Branded keywords are good to use in the emails “from” name and can be used in the subject line as well.

    2.  Compelling

    One of the steps in our 8 Step Call to Action Guide is to make calls to action compelling and it’s no different with subject lines. You only have a couple seconds to grab the attention of people skimming through their inbox. Make sure you include the email’s offer in the subject line, so people know the value the email will provide them. Creating a sense of urgency is a good tactic to use in conjunction with the compelling offer.

    One way to do this is to use brackets in the subject line. For example, you might be promoting an upcoming webinar and you want to make sure recipients realize this right away. Your subject line could be, “Learn to Become an Efficient Blogger [Webinar in Two Days]

    3.  Spammy

    You can’t afford to have your subject line get caught in spam or firewall filters. Therefore, you should be very careful when choosing what words you put in the subject line. Words like free, act now, offer, or credit will almost always get flagged by spam filters.

    You shouldn’t have words in all caps and don’t use punctuation in your subject line.  During the upcoming webinar series Jeanne and I will share resources that will help you ensure your subject lines aren’t spammy.

    4.  Consistent

    The two things people will see before they even open your email is the subject line and the first sentence or two in the email. This is because most people use the preview function in their email client to determine if they want to spend the time reading the email.

    You want to keep the first couple sentences very consistent with the email's subject line. They should reinforce and add to the compelling offer and should be action-oriented. I recommend including a link in the first or second sentence that sends them to the page you want them to take action on.

    5.  Short

    Email subject lines cannot be very long. I recommend you keep them under 45 characters or you run the risk of people not seeing the entire subject line. You also want to put the most important and compelling information in the beginning of every subject line.

    The best way to determine what effective subject line will be effective is by testing different subject lines. Don’t worry, we’ll be covering email and subject line testing during the upcoming email marketing webinar series.


    Photo credit: derekfredrickson.com


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