How to Write Catchy E-mail Subject Lines and Increase Open Rates (Via MailMunch)

Last updated: 
June 10, 2022

The CURVE formula for writing catchy e-mail subject lines

Your e-mail subject line is the most important part of your entire e-mail. It will determine whether or not that e-mail gets opened. If you do it right – more people will open your e-mails and, luckily, you will get higher click-through rates, traffic and sales from your e-mail marketing campaigns. If you do it wrong – people won’t open your e-mails and you will fail to lead to your website and convert them into customers. Since this element is so critical for the success of your business, we decided to create an entire post on the topic and teach you how to write catchy e-mail subject lines.

The C.U.R.V.E. formula for writing catchy e-mail subject lines

Alex Williams, the Creative Director & Digital Strategy Director at Trendline Interactive, spent years writing and testing e-mail subject lines for all kinds of business clients.Based on his experience, he created the C.U.R.V.E. formula, which allows him to create catchy e-mail subject lines that get opened almost every single time.In this case, C.U.R.V.E. stands for Curiosity, Urgency, Relevancy, Value and Emotion.

According to this expert, a good subject line must have at least two of the five C.U.R.V.E. elements to get more people to open their e-mails. Let’s cover this formula in further detail:Curiosity – how do you make people curious about the content you’re about to share? One of the ways you can do this is to ask them a question they would like to know the answer to. Be sure to use open questions, not yes/no questions. Bad example: Are you ready for winter? Good example: What does reading books have to do with being successful?

You must be very careful when using curiosity in your subject lines. You don’t want to mislead and trick people into opening your e-mail and then not deliver on your promise. This will destroy the trust they have in you and will decrease your engagement with your e-mail list in the long term.

Urgency – this element explains why your subscriber needs to open your e-mail right now. In other words, that their delayed action may result in them missing out on an amazing offer or opportunity. This could be anything from: A discount or special offer, a free live event like a webinar or hangout, offering a training program or product for a limited time only, having a limited number of spots or items available for sale, news/tips related to a current event/situation. In any case, you will produce far better results for your business if you ask for immediate action from your subscribers.

Keep in mind that urgency is only powerful when it’s associated with relevancy and/or value. Discounts for things people don’t need and are not relevant to them are not only useless, but they will also damage your brand in the long term.

Relevancy – the content that you send your subscribers must be relevant to their interests, demands and needs. This sounds good in theory, but it’s harder to do it in practice. It starts with gathering data about your subscribers. What are their needs, wants, inspirations, fears, frustrations? What do they care about? Keep in mind that people change. What’s relevant to them today might not be relevant next month. So, always keep your information up-to-date to make sure you know exactly how the needs of your audience are changing. Always connect your messages to the core values of your company.

That’s why people follow you in the first place, and this is what matter to your ideal subscribers. You can further increase relevance by segmenting your subscribers in groups based on additional interests and differences. The final step is to run behavior triggered e-mails sent based on the content they view on your website, the e-mails they have opened before, the sign-up offer they opted into. Value – your subscribers follow you in the first place because there is something valuable you can offer them.This could be in terms of information, product deals or anything else they desire. In the end, they want to solve a specific problem or reach a specific outcome and you’re the one that can help them.If you want to build great relationships with your list, you must always provide value and ask for very little in return.If you don’t know what people value, you must get to know your customers better and find out. That’s the only way to be successful in business.    

Emotion – the decisions that people make are more based on emotions that logic. That’s why it’s so important to trigger the right emotions in people, thus driving them to take action and open your e-mail. One of the best ways to do that is to use sensory language. To do that, you must use words that connect with the five human senses (sight, sound, touch, taste, and smell).

Here are some examples:

Sight – You haven’t seen anything like this before

Sound – How many times have you heard these three words?

Touch – Why do we feel so bad after a breakup?

Taste – Nothing tastes better than a fresh macaroni pizza

Smell – Does your bathroom smell bad? Here’s what to do.

In addition to the senses, you should know that different words have different emotional value.

The so-called power words have 10 times or even 100 times more emotional value than average words. Even words that have similar meanings or the same meaning can have different emotional value. For example, the word “cheat” is considered to be more powerful than the word “unfaithful.”

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Some additional tips for writing great e-mail subject lines

The C.U.R.V.E. formula provides you with a base for creating amazing subject lines. But what else can you do to further optimize your subject lines for success? Here are some additional tips you can try:

Keep it short – most e-mail clients display up to 60 characters in the subject line.

Mobile phones show even less – between 25-30 characters. So, be sure to keep your subject lines short, otherwise your audience won’t be able to read them.

Subject line too long

Short subject lines have another benefit: they usually draw more attention and stand out because most people are more likely to use longer subject lines. Place the most important words at the beginning – 53% of e-mails today are read on mobile. Since you don’t know how much of your subject line will be displayed, it makes sense to put the most important information first. Furthermore, this will allow you to catch your audience’s attention much more easily. After all, people tend to read from left to right. Eliminate filler words – any words that don’t have a purpose or don’t help you accomplish the goal of your e-mail should simply be eliminated. This category includes words like “nice to meet you,” “thanks,” etc.

Before you put a word in your subject line, ask yourself the following questions: Do I need to include this here? Does it help me get more people to open my e-mail? Or can I just use it in the body itself? Personalize your e-mails – one great way to do this is to simply use the name of your receiver in the subject line. Avoid words like “dear,” “Mr.,” “Mrs.” – they are not specific enough. Alternatively, you can also use the person’s company or website name. Most e-mail software providers, such as MailChimp, GetResponse and Aweber, provide you with options for personalizing your e-mails and using dynamic content. Basically, inside the e-mail and in the subject line itself, you can place a short code that will be replaced based on the information that you have provided for that subscriber in a certain field in your database.

You can use your subscriber’s name or their company name in the e-mail to get their attention and make them even more interested in what you have to say.Be clear and specific about the topic of the e-mail – more often than not, it is better to be super clear in your subject line regarding what is the e-mail about.

Specific subject line

This allows your subscribers to determine how important your e-mail is to them and whether to open it. Keep it simple and focused on what action you want your customer to take. If you include too many things, your reader might get confused and your value proposition will make less sense for them.

Other smart ways to increase open rates even more

Beyond just writing a great subject line, there are several other things you can do to further increase your chances of your e-mail being read: Send e-mails at the right time – this is one element that has nothing to do with how good your subject line is, but it has a major effect on how many people will open your e-mail. So, when is the best time to send e-mails? This largely depends on your industry and when your subscribers are most likely to read their e-mails. Rick Stamberger got 70% higher open rates when sending e-mails to restaurateurs after the lunch-hour rush. So, your best option is to get to know your audience’s habits and test to see when they’re most likely to open their e-mails. Still, there are some universal rules that you can start with.

According to KISSmetrics, open rates are higher during the weekend and early in the morning. Keep in mind that some people on your e-mail list might be from a different time zone, so consider that factor when sending your newsletter. If you’re using MailChimp or GetResponse, you can send your newsletter and get your subscribers to receive it at their local time, which can greatly boost your open rates. Write an engaging first sentence – with most e-mail clients, your subscribers will be able to read your first sentence or so without even opening your e-mail. This means that you can further use this as an opportunity to encourage them to click and open your e-mail. So, how do you do that?

First, refer to them by their first name. Studies show that using the name of your subscriber tends to increase open rates. Second, make it about them and the value they are going to receive from reading your e-mail. Apply the same principles from C.U.R.V.E., just expand on them. Here is some great example: “Hey Martin, This guy has made $42 million online. He just launched a new…” You can also implement urgency in your first sentence like this: “Quick:”, “There are only two hours left.”, “Last chance to get…”

A/B test subject lines – even with years of experience in the field, you’ll never know exactly which subject line will perform better.That’s why it’s a smart idea to test several variations on a small portion of your list before sending it to everybody else. To do that, you’ll need a software that will allow you to do so – like MailChimp or GetResponse. Keep in mind that you still need to send your e-mail to enough people to get accurate data. We suggest testing by sending one version to at least 100 people. Consider the sender’s name – sometimes, the person who sends the e-mail matters even more than the subject line itself.

People are more likely to open an e-mail from someone they already consider an authority and an expert than someone they’ve never heard of. If the CEO of the company sends an e-mail to the list, people will be more likely to open it. If you receive an e-mail from someone who you know delivers great content and will provide you with great value, you will probably open it.

Frank Kern authority: I always read e-mails from Frank Kern, because I know he only shares amazing content.

Avoid words that trigger spam filters – MailChimp has run analysis on millions of e-mails and found out that there are certain words that are more likely to send your e-mail straight to the spam folder. Where it is very unlikely to be read. Be sure to avoid sales and overused words (Free, Help, Reminder, Percentage off, etc.). In general, anything that is associated with sales.

In conclusion: Writing great subject lines is an art and a science. This post will help you get started by knowing the basics, but you need to put in some extra effort to test out different versions, get to know your audience, and see what works for your business.

Credit: Martin Shel via MailMunch

By Allan Levy

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