What are best practices for email subject lines?

Make the Most of Your Preheader

The top piece of advice I can give for writing a great subject line is to make the most of the preheader.

What is a preheader? It’s the text that often comes after or under the subject, and if utilized correctly, it can increase the effectiveness of a subject line by leaps and bounds. So always think of them as a pair, like a great couple. They should complement each other.

Share Your Value Proposition

First thing on my list when I create a subject line is to first determine my client’s value proposition, then highlight it. That way, I’d be able to catch the audience’s attention and entice them to open our email.

I approach this by focusing on a specific benefit that their products can provide, such as free shipping, a discount, or a limited-time offer. This way, it helps me communicate the value of our offer and encourages readers to click on our CTA (Call to Action – Button on your email), which will take them to my client’s website to take advantage of the offer.

Another approach is to appeal to the emotions and desires of the target audience. Let’s say my client sells fashion accessories; I might use subject lines such as “Upgrade your style with our latest collection” or “Get noticed with our statement pieces,” tapping into my client’s audience’s desire to look and feel their best. This way, I also create a sense of excitement and anticipation for what’s inside our email.

Rely on a Marketing Platform

To generate leads and sales through digital channels for a small business with a budget of $5,000 per month, the recommended approach includes allocating funds towards email marketing using a platform like Klaviyo to send personalized and targeted emails to subscribers, as well as paid search and social media advertising to reach new potential customers.

Continuous monitoring and data-driven decision-making would be employed to ensure the effective use of the budget. Additionally, some budgets could be allocated toward search engine optimization (SEO) and content marketing to improve organic visibility and website traffic.

Speak Your Own (Brand’s) Language

One of the most overlooked best practices for subject lines is not to forget to speak your brand’s language and do it constantly. It is easy to get into the loop of creating “one-size-fits-all” subject lines that are proven to work, such as: “Oh, you’ve forgotten to check out” or “Welcome to XYZ team” or “We’ve missed you.”

Try to step back and analyze EVERY SUBJECT LINE of EVERY EMAIL YOU SEND. It should have the same brand voice as, for example, your tweets or parts of your IG captions.

Your subscribers should know from the subject lines that it is your brand that is emailing—without even being transparent about it. From this stage, be open to testing out other elements (long vs. short, numbers vs. no numbers, etc.), but keep in mind: speak your brand’s language.

A/B Test Your Subject Lines

When you’re first delving into email marketing, you’re going to want to test your subject lines (and preview text). Doing this will help you find out what resonates with your customers and will improve your open rates.

Testing and tracking are two of the most important things to do in marketing—and in subject lines, you can test anything from length, to capitalization, to emoji use!

Don’t Be Afraid of Emojis

When I open my inbox, less than 20% of the emails I receive use an emoji, which means they still provide a reasonable opportunity to stand out. Emojis help infuse some personality into your copy, as well as adding color that can draw the eye of a reader opening their inbox.

Write Within 3-5 Words to Increase Open Rates

Shorter email subject lines, like 3-5 words long, can lead to higher open rates because they are easier to read.

Additionally, using “power words” such as “urgent,” “limited time,” or “exclusive” can grab the recipient’s attention and make them more likely to open the email. However, using these tactics sparingly is essential as avoiding clickbait-style subject lines that over-promise and under-deliver is essential, as this can harm your credibility and damage your relationship with your subscribers.

Match Your Headline With Your Email Copy for Uniformity

Making your headline make sense means you also need to tailor-fit it to your email copy without revealing too much. It’s supposed to be a tease to what the reader is getting in your email copy, and having uniformity from the subject line to the email body makes your email stand out and not be spammy.

Cross-pollinate With Unrelated Industries

Rather than tweaking your subject line for incremental gains, jump industries instead. Subscribe to newsletters in various sectors such as real estate, fashion, software, sports, solar energy, etc., and observe. Here’s what you do:

1. Flag any subject line that catches your attention.
2. Adapt to your own business.
3. Send it.

Here’s a sneaky tip: Don’t sleep on those boring “transaction” emails from social media. A dull “Mark just sent you a message” can be turned into “Your 401K just sent you a message” or even “The Treadmill Wants to Chat!

Try the “From the CEO” Subject Line Technique

Using a personal note from the CEO as a subject line can be a game-changer in your email marketing strategy. It creates a sense of authenticity and connection with your subscribers, making them feel valued and heard.

By using the CEO’s name and personalizing the subject line, you create a sense of importance and urgency, driving higher open rates and engagement. This technique highlights the human side of your brand, adding a personal touch that resonates with your audience.

In today’s digital age, where face-to-face interaction is limited, using a personal note from the CEO in your email subject line can make all the difference in building trust and loyalty with your subscribers. (Don’t overdo it!)

Approach With Curiosity

A brilliant strategy for subject lines is making them have curiosity embedded in it. An example would be to include the name of the person, company, and pain point as the receiver to get their attention.

One way to make them curious is to ask a question that would make them wonder. This can be, “Have you seen this yet, NAME?”

One of my favorites is the unfinished question that goes, “What will it take to help you get..?” In order to be interesting, you have to be interested… you have to get them curious in order to open your mail.

Test Your Send Times

Testing the send time of an email is important for measuring the results so we can know which subject line works and which one doesn’t. Even the most catchy, short, sweet, personalized subject line can be a failure if we email at the wrong time.

To prevent this from happening, we should send emails when our users are most active, and the chances of engagement are high. We can measure this with a lot of testing (sending the same email on different days/hours), or with Send Time Optimization features, like Einstein Send Time Optimization – the Salesforce Marketing Cloud solution.