Ultimate Guide To Email Marketing Subject Lines

GlockApps (G-Lock Software)
5 min readSep 29, 2021


If you’re an email marketer or considering becoming one, you’re probably curious about what motivates consumers or subscribers to open the emails that you send to them. If you want to increase your open rates, what are the principles you need to master as an email marketer? All of this boils down to the first important factor you should know before crafting a successful email: your email subject lines.

The first impression is crucial when you’re trying to sell your products and services. You must have an effective introduction to your email or everything else can fall apart. Make a habit of delivering subject lines that your recipients cannot resist and your brand will surely stand out from the crowd in your recipient’s inboxes.

Rule №1: without an impressive or catchy email subject line, all your email marketing efforts and strategies will go to waste as your emails will be ignored, resulting in low open rates and possibly affecting your deliverability rate.

This brief guide explains how you can easily start writing powerful subject lines that actually work!

How to Personalize Your Email Subject Lines

A huge percentage of email recipients open their email just by looking at the email’s subject lines, and also, because of that, subject lines are one of the main indicators that email providers use to decide if an email should be tagged as spam. This means that email marketers should be careful in choosing the right set of words for their subject line since it is powerful enough to make you or break you. The balance lies in being attractive enough to catch the attention of the audience without being spammy.

One of the most effective things you can do is to personalize your emails. Did you know that aside from being precise and on point, creating a personalized email increases open rates by 20%?

How do I personalize my email campaigns?

Utilizing your subscriber’s name is one way of making it casual and a bit personal for your recipients. It also makes them feel valued and heard. This could cater to the emotions of your subscriber. However, it is not always about the recipient’s name…

❖ Creating a personalized email can also include trendy emojis, but don’t overdo it. You can use just one or two emojis to get your subscriber’s attention.

Birthday Greetings and Anniversaries of being a loyal subscriber. This can build trust in your brand and the email is more likely to be opened. Make your readers feel special and appreciated, and they will reciprocate. This tactic can drastically affect open rates and boosts customer engagement.

Mention their transaction history. Your email subject line can consist of a promo that you give to someone who recently purchased a selection from your shop. (e.g., Because you bought X, we think you’ll love Z…)

❖ Another clever method is calling the recipients by nicknames or something unique that makes them feel like part of the club. A level of trust and curiosity can be built that will result in great open rates. A great subject line is all about uniqueness, so make them feel special. Here are some subject line examples for you:

ColourPop Cosmetics says — Hey Chloe! Trust us, you don’t want to miss this!

BirchBox says — Hey Champ! We think you deserve this gift from us…

Torrid says — Hi Chloe, are you ready for new magical movies from Disney?

How to Make Email Subject Lines Relevant

These are the fundamentals of a relevant email subject line. Familiarize yourself with these principles and you’ll be one step ahead of most email marketers.

Urgency is a Must

Convey urgency in your call-to-action (CTA) phrases to encourage your audiences to open your email because there’s something significant that requires their immediate attention. Fear of missing out (FOMO) is a great motivator in a consumer’s decision-making process.

Make Them Curious

Create something catchy in the form of a mystery or a question that can only be answered by opening your email to get more information. Make sure not to overdo it as it may end up in the spam folder.


Subscribers like to be informed. Use timely and trending topics that can be associated with your brand while adding value and freshness to your content. Engage your audience in interesting ways but don’t overwhelm them with excessive information. Strive to be selective and opportune.

Put Some Recognizable Names

People are always attracted to celebrities and influencers. When possible, incorporate content that involves famous people relatable to your subscriber’s interests. However, make sure that the content is still relevant to your products and services. This direction is not compatible with all industries. You must respect the tone of your brand and never overreach as it can be perceived as a gimmick.

Tell Cool Stories

A compelling story can provide an extra push to your open rates and spark the sensibilities of your recipients. If a subject line suggests that your email contains a compelling story, your recipients will be more eager to open it and be on board with reading a bit more than usual. The more you understand your audience’s interests, the more relevant your stories can be.

Promos / Offers

Consumers love freebies and discounts. Create catchy promotions that can be incorporated into your subject lines and your open rates will go through the roof. Don’t overdo these so the perceived value of your products and services stays high. If your audience gets used to frequent discounts they are more likely to procrastinate in their decision making. Remember that instilling a sense of urgency is one of the more powerful tactics you can use to write a successful email subject line.

7 Tips for Writing Email Subject Lines that Work

  1. AVOID ALL CAPS subject lines, please — This will get you nothing but spam-tagged emails. Be aware of when to use capital letters to gain the attention of your subscribers. A lot of people perceive all caps as unprofessional and often associate it with being yelled at. Studies show that most email readers prefer emails written in lowercase letters. When in doubt, it’s advisable to run a spam checker tool to make sure that your emails are on the safe side.
  2. Be concise — Not all email recipients check and read every single email they receive. Composing a direct and clear message gives you a better chance of cutting through the inbox noise and gaining the attention of recipients with a short attention span. This type of reader usually scans emails very quickly and only stops to read the ones that appear to be important. Your goal is to write a subject line that stands out as important and/or a must-read.
  3. Be transparent — Let them know your email’s content quickly. Don’t confuse your readers and never promise something you can’t deliver or you will lose your audience’s trust in the blink of an eye.

Read the full story at GlockApps blog.



GlockApps (G-Lock Software)

Email marketing & email deliverability tips and best practices. Are your emails getting into your customers Inbox? Find out now! https://glockapps.com