Newsletter subject line: how to make customers curious

Newsletter marketing offers a relatively simple way to address a large group of customers in a targeted manner, to make them aware of your web project. Often, however, little effort is invested into the first thing that catches the recipient’s eye: the newsletter subject line. If you make the subject line appealing and original, customers will be more likely to open the newsletter. Subject lines that are too cryptic or gimmicky could mean your newsletter is simply deleted and never read.

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Creative newsletter marketing is worth it

Firstly, to attract the attention of the target group, and then to turn those interested into customers, a company needs to have a well thought-out online marketing strategy to ensure lasting customer loyalty. Good newsletter marketing is therefore an essential component of successful online advertising, since it offers very clear advantages when combined with measures such as SEO, SEA, link marketing, and the use of multimedia content:

  • It is comparatively cost-effective and can be combined with easy-to-use newsletter tools.
  • It is based on the customer’s prior consent e.g. through the double-opt-in procedure, and therefore can be trusted, unlike spam. 
  • Newsletters automatically end up in the recipient’s inbox and can present offers and information quickly, directly, and conspicuously.
  • Since users usually have to register on your site to receive a newsletter, you often have information on how you can customize the newsletter to them (so you can address prospective customers and new customers differently to how you would address regular customers).
  • Analysis tools allow you to measure key KPIs, such as the opening rate, click-through rate, and bounce rate of the newsletter and, for example, how to use A/B tests and adapt content to optimize your newsletter campaign.

However, newsletter marketing doesn’t come without its problems: because of the influx of messages and advertisements that land in inboxes every day, most users tend to be quite strict when it comes to filtering out e-mails from companies – sometimes deciding within seconds whether an e-mail is worth opening or should be immediately deleted. If the subject line of your newsletter is boring, annoying, or even offensive, it will immediately land in the recycle bin, the automated spam filter, or the recipient will simply unsubscribe. In the case of newsletter marketing, you’re also competing with all other e-mail marketers who send out newsletters. Since you don’t get a second chance to make a first impression, you should familiarize yourself with a few basic rules on how to make your subject lines interesting and encourage customers to continue reading.

A good newsletter subject line is a basic need for marketing success

The subject line of your newsletter is the first thing that the reader will see in their inbox. However, is it possible to get customers interested in your own company, product, or offer just by sending promotional e-mails? The key to this lies in a subject line that is well thought-out and appealingly designed. Apart from the appropriate optical layout, there are four essential elements:

  • Good content
  • Correct addressing
  • Clear design
  • Appropriate length

Since the subject line is the first thing that a customer sees from your company, and ultimately what makes them decide whether to read or ignore it, you need to make sure that it doesn’t contain any errors. If the content, addressing, presentation, and length of the newsletter subject line are as accurate as possible, as well as clear and useful, you increase the chance of more conversions.

This is how you can optimize your newsletter subject line

You won’t be successful if you don’t constantly optimize your newsletters, especially their subject lines. There are some adjustments that writers can make, so here’s how to make the subject line reader-friendly and meaningful:

Choosing the right length

The subject line of each newsletter has the disadvantage in that it offers very little space for meaningful content. In the subject field, there’s enough room about for 30 to 70 characters, depending on whether it is viewed on a desktop or mobile device. Since the text will be cut off if it’s any longer, it is advisable to not exceed the maximum length of 30 to 50 characters, to make sure the whole subject line can be read regardless of the device it’s viewed on. Some e-mail clients even display the first few lines of the newsletter (around 80 characters) as a preview ('preheader'). In any case, you should put the most important information and keywords at the beginning of the subject line so that they are seen first.

Creating interesting content

With the right mix of information, entertainment, and advertising, you can make your newsletter stand out from the competition and awaken interest in your product or service. This should also be reflected in your newsletter’s subject line. So be calm, creative, and make it obvious what the newsletter is about. If possible, adapt the subject line to the style of your newsletter and get potential customers interested in your product or service.


'Cheap dream vacation from '1001 nights''

Be precise and understandable

The subject line of your newsletter should clarify what the content is about. The user wants to know whether it is worth opening the e-mail instead of sending it straight to the recycle bin. If the subject line is incomprehensible or promises content that does not appear in the e-mail, you will quickly lose a potential customer. An error-free, compact, and meaningful subject line is more likely to win people over. With concise facts and important information e.g. special deals for a limited time or discounts, you also keep the reader’s interest.


'XY frying pan: non-toxic 5 year guarantee '

'Only until 31.01: free tax consulting'

Use the appropriate symbols

You can use Unicode® characters or emojis to improve the structure of your web offer and break it up a bit. These can help generate and maintain attention, but also come with risks: only use these special characters when they add value to your project, otherwise they come across as spam, and aren’t displayed correctly by all e-mail clients. Therefore, you have to consider whether it makes sense to use them in your newsletter.

Examples of popular special characters:

Symbols and emojis ( ❤✆✈★☺) as supporting characters for specific topics: '♥ LOVE POWER: free dates for 5 days ♥'

Circular numbers (➊➋➌) for lists such as: '❿ tips for a perfect garden'

Checks (☑) for visual emphasis on structure, overview, and reliability: 'XY electricity tariffs: clean cheap good '

Arrows / direction symbols (Ƅ¢Üð) to direct the reader’s view to specific terms: 'Now Æ summer sunglasses Å 50% cheaper'

No-gos: what doesn’t belong in the newsletter subject line

Now that you have a good understanding of what belongs in a newsletter subject line, you will know why the following should never be included:

Boring and general wording

Nothing lands in the recycling bin faster than a newsletter with an uninspiring subject. If you want to catch the reader’s attention, you need to make the newsletter as interesting as possible and know which topics will win your target group over. Monosyllabic or generic subject lines won’t impress.


'Company Boring: newsletter 01/2017'

Cryptic language

Creativity and originality are welcome in the newsletter subject line. However, make sure you don’t go overboard or use language that’s too complicated. Using too many characters, insider terms, abbreviations, or abstract expressions aren’t recommended, since the customer might not be able to work out what your newsletter is about. More details can be included in the text body if need be. Incorrect spelling, missing words, and false information are also taboo.


'☒Network adapter/Interface.(IEEE 1394)☒'

'Right now /// 10% discount on cotton socks'

Spam terms and advertising

You should pay close attention to your choice of words in the subject line. Certain symbols aren’t displayed correctly by some clients or are directly classified as 'junk mail'. If you think you’re one step ahead of the competition by using crazy slogans, modern spam filters are designed to detect certain word combinations and often remove them before the customer has had a chance to see them. You will notice this due to the low opening rate. Typical spam characteristics include the excessive use of intrusive phrases, as well as uppercase letters, exclamation marks, spaces, symbols, and commercial terms.



'♥♥♥HOT DATES for one night♥♥♥'

'Get cash quickly!!!!!!!!'

'$$$ Earn money right now $$$'

'What are you waiting for???'

'Important message for you!'

'Get it now!'

'Click HERE ☞☞☞'

Unnecessary duplication and repetition

You shouldn’t write the sender, recipient, or company name twice. It’s not necessary since they are usually included in the header. In addition, repeating words means you have less character space.


'Winter holiday with XY travel operator'

(The name of the travel operator doesn’t need to be mentioned here since this name will be shown as the sender).

Good subject line = more conversions

Your e-mails are designed to help you increase your reach and revenue. KPIs (Key Performance Indicators) reveal the success of a newsletter or e-mail campaign. The main KPIs in e-mail marketing are click-through rates and opening rates. The aim of your e-mail strategy should be to persuade customers to open the newsletters, to impress readers with content, and to create the basis for more conversions.

To achieve this goal, it is important to continually optimize the content and design of your newsletter’s subject line and to keep central points in mind. As far as the ideal subject line is concerned, here is a summary of the most important points. Subject lines should:

  • Give the most important information in a direct way
  • Make it clear what the added value and benefits of your offer are
  • Be the first port of call to make readers interested in your offer, information, or products
  • Be straightforward, clear, and as precise as possible for each inbox 
  • Not contain dubious wording

There’s no one-size-fits-all method for the perfect newsletter subject line, since every product, every offer, and every target group, is different. In principle, however: Make your newsletter as appealing, comprehensible, and original as possible. Don’t be discouraged when things go wrong, since even newsletters need to be constantly optimized. If you’re creative, provide accurate information, and know a lot about your own offer, you can stand out from the crowd and gain the interest of potential customers.

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