The Reality Behind Email Subject Lines

    Last updated: July 17, 2023

    Many of our clients have expressed interest in email subject lines. Specifically, what strategies will grab customers’ attention and improve e-promo efforts. Focusing our report specifically on newsletter emails, we analyzed almost 1,000 email deployments of the top 25 senders from Omeda’s Email Builder platform. Open Rates seemed to be the best indicator of subject line success. However, keep in mind that there are a lot of other factors that contribute to high open rates and overall e-promo success along with a strong subject line. Some of the main findings from the data analysis are below.

    1. There Is No Such Thing as Email Subject Line Buzzwords

    We split the emails into two categories, those with over 20 percent open rates and those with under 20 percent open rates. We then looked at the words that were included in these two categories. Through the analysis, keyword trends affecting subject line success were hard to come by. There simply weren’t  buzzwords that guaranteed success on email campaigns. There also weren’t words that jumped out as verbiage that was hurting the email campaigns. Many words and phrases – such as “tips” and “best” appeared in both categories, the over 20 percent engaged newsletters and those below that 20 percent threshold. What appeared to be more important was the topic highlighted in the subject line and if that topic was of interest to the audience the email was sent to.

    2. More Detailed, Specific Subject Lines Perform Better than Generic Prose

    From a general review, subject lines that sounded more interesting seemed to trend higher in terms of open rates vs. more generic lines. Whether it was having a leading subject line, making the line a question or including more of a detailed overview, thought provoking content generated more opens. As an example, say you had an article written on the benefits of coffee. Rather than saying “Top 10 Benefits of Coffee,” options that may improve engagement could be something like: “What Beverage Is Linked to a Longer Lifespan?” or “More Antioxidants, a Memory Booster, and Good for Your Liver and Heart – Coffee Is Much More than a Caffeine Kick.” Putting a little personality or providing information that will spark curiosity can help the success of e-promo campaign open rates.

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    3. Subject Lines Aside, the Content and Cadence of Your Emails Plays a Large Effect on Opens

    One of our clients was a very interesting case point for our analysis. The company has a newsletter that they send out twice a day – once in the morning and once in the afternoon – highlighting local news from that day. The morning and afternoon emails are sent at approximately the same time every day with a consistent subject line for each of them. These two email campaigns have total open rates of 44 and 45 percent, both in the top 10 for open rates out of all emails sent. A main factor as to why this particular newsletter is so successful is because the information being provided is under the breaking news category vs. the strategic content category. In general, breaking news will be of more interest than other content in emails sent out. Most consumers want to know the current events happening in real time; the content is important to them and so is the timing of when it is delivered.

    Strategic email newsletters can still use breaking news updates for key learning opportunities. In the example above, the information being provided to customers is exactly what they are interested in. More than that, customer recipients have come to expect these emails on a daily basis because of the consistent email schedule. This is an important reminder as marketers that a subject line is only a small part to a successful email campaign. Major factors that are contributing to strong open rates are knowing your audience, catering to their preferences and interests and delivering the information at the right time.

    4. Smaller, More Targeted Audience Lists Resulted in Better Open Rates

    While analyzing the data, it was obvious that two of our clients were performing exceptionally well with their email open percentages. Their open rates were hitting anywhere from 37 to 49 percent and they took up the majority of the top 50 emails opened. Taking a look at their audience size, they were on the lower end of the spectrum. In contrast, two of the bottom performing companies, comprising of the 50 lowest performing campaigns, had an audience size that was eight to ten times larger than the top performers. These email campaigns had open rates that ranged from one to seven percent. As the open percentages started to increase, the number of delivered emails began to decline on average. This isn’t to say that if you send your email to an audience that is smaller, it will return 50 percent open rates. Rather, the results are displaying that your audience’s interests matter. The larger the audience, the more difficult it is to send targeted content to your customers. Companies that had smaller audiences were able to effectively target with information that was relevant for the receivers.

    With these witnessed trends, how do CPM rates and email advertising come into play? When advertising dollars depend on how large of an audience you’re reaching, cleansing your audience list and eliminating unengaged members doesn’t make a lot of sense. However, that doesn’t mean you can’t use targeted messaging to better reach and resonate with the email recipients. One tactic could be to keep the full list of customers, and to split them up into different categories to call out better-tailored content. For example, one way to split would be by job position. Customers in C-level and executive positions are going to be interested in different subjects than new associates. Keeping the content in the email the same, but calling out different points of interest in the subject line for the two groups could result in better open rates overall for the deployment.

    Overall, the results of the newsletter campaign explorations are highlighting that the subject line in an email deployment may not be as important as other factors such as the audience you are sending it to. A subject line can be an additional tool for increasing engagement, but it will only be effective if the information is interesting and relevant to the recipients. Rather than trying to get a quick fix for subject lines that will improve e-promo campaigns, take the time to invest in the audiences you are trying to reach. Think about who you’re sending the emails to. Do they care about the subject of the content they’re receiving? Are they currently engaged in your email promotions? Are you sending the emails at the right time? What will make them interested in reading what you’re sending?

    In the coming weeks, we will be detailing WHY it is important to cleanse your audience list, keep engagement numbers up and come up with an overall strategy for e-promo campaigns. Then we will dive into HOW you can do this to ensure your audience is engaged and interested in the content they are receiving. In the meantime, please reach out to us at if you are interested in learning more about email engagement.

    Photo by Leyre Labarga on Unsplash

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