What Not To Do When Creating Your Subject Lines

The Subject line is often the last thing you think of before sending your email newsletter but it’s the first thing your recipients see after getting your email.

Every day Inbox is full of personal messages, subscription newsletters, and regular spam emails which all compete for the reader’s attention. This means you have to work harder at your Subject lines to grab the recipient’s eyes.

Here you can find general tips on how you can increase your email open rate by using the right Subject line.

In today’s article, I’ll focus at the most important aspects email marketers can’t ignore when writing their Subject lines:

1. Irrelevant or Excessive Personalization

Email marketers often think that the recipient’s name in the Subject line help them make their commercial email look like a personal email from a good friend. That’s true when the personalization is used wisely and here you can learn about different ways to personalize the Subject line.

Before you use the mail-merge option in your bulk email software, you’ll want to make sure you have the recipients’ names in your database. If you build an email list using an opt-in form on your website, add a “Name” field to the subscribe form and force people to provide their name.

If you don’t require the subscribers to supply their names, you may end with a Subject like this: “Hi {!firstname_fix}, Last Chance for Your Free Copy…”

Even if the name is required, many people who want to keep their anonymity will type their nicknames, or nonsense “abcabc” or “bgfbggg”. Will your Subject line look good if you merge such a “name” into it?

The lesson is: Don’t rely on the name in the Subject line. Instead of blindly stamping a name into every other Subject line, write an appealing Subject that speaks to the recipient’s best interests.

2. Unlimited Urgency

Everybody likes offers, gifts, discounts and the like. For this reason email marketers often includes their exclusive proposals into the Subject line in the hope to catch the reader’s attention immediately. That’s a good idea. And to make it work better, you’ll want to state a time limit for your offer in your Subject.

For example, “50% Off for ANY Of My Products” is good but “Only BEFORE Christmas You Can Get 50% Off for ANY Of My Products – Your Exclusive Coupon Inside” is better.

Why is a time limit important? It forces the reader to act before the “gates” close. If the reader doesn’t open the email immediately, he will not know when the offer ends. It may happen he’s ready to take it but the discount has already expired. You get one unhappy customer and you lose sales. 

The lesson is: State a time limit for your offer in your Subject line even if it never expires. Or, at least mention that your offer is time-limited. This makes the recipient act fast on your offer.

3. Subject Line Length

You probably heard the opinion that the ideal length of the Subject line is 50-70 characters. That’s because many email clients will cut off Subject lines at 50 to 70 characters. With this limit, each character counts and you’ll want to make sure that your most important information fits 50-70 characters.

However, now many email clients allow up to 100 characters in the Subject to be visible and the recipients can also choose how they will view the email Subject when they setup their email client. Some email programs will show truncated characters if you hover the mouse over them or allow the recipients extend the Subject line field. This means you have more space to write your Subject line and may not stick to the strict 50-70 characters limitation.

The main task of the Subject line is to make the recipient open the message. But the research shows that the Subject line also affects click and click-to-open rates. The percent of recipients who click on the link in the email after opening it depends on the length of the Subject line, in particular:

– shorter Subject lines lead to higher open rates, but lower click-to-open rates;

– longer Subject lines generate a lower open rate but a higher click-to-open rate that is an indication of real relevance of the offer to the user’s expectations.

Why is this? Ambiguous and obscure Subject lines often attract the reader’s attention and people open the email to find out what’s in it. This technique is often used by spammers. Short Subject lines are more likely to be ambiguous or intriguing than long ones and they get a higher open rate.

So, more people open the email with a shorter Subject line but are they the right customers?

Here are two different Subject lines for the same email copy:

1. “Free shipping today only!” 

2. “Summer Starts Today: Mountain Bikes & Accessories with 20% off, plus free shipping”

The Subject line 1 is likely to generate a higher open rate because it excites the reader’s curiosity what you will ship them for free. But if they are not interested in mountain bikes, an open will not drive a click.

Relevant customers – those who are really interested in your offer – may not realize that the email with the Subject 1 contains a proposal of interest to them, and may not open the message at all, and therefore will not click. Relevant customers will most likely open the email with the Subject line 2 and click on the link inside the email.

Thus, longer, more specific Subject lines seem to be more attractive for relevant customers and effective for driving an action.

However, if your email contains a single strong and valuable proposition, a short Subject line that clearly conveys the content is good, for example “Mountain Bikes with 20% off”.

The lesson is: Don’t take the Subject line length as priority. Compose your Subject in the way it appeals to the best interests of your relevant customers.

4. Branding is Not Enough

Is your brand name in the Subject line enough to make the recipient open your email? I don’t think so especially if you email them daily or weekly. In addition, doesn’t your From field represent your company?

If you email daily, you probably spend just a few minutes to write a Subject line. But it doesn’t entice the reader to open the email. If your Subjects are the same from email to email, the recipient loses interest quickly and your brand name is not the driver that can make them open the message.

So, instead of writing “[Company]: January 25, 2010 – News & Updates” in each letter, use your top story as your Subject line. The Subjects like below let you know about something good, new, exclusive and timely to read:

[G-Lock EasyMail]: Follow These Magical Steps to Boost Your Deliverability
[Fast Blog Finder]: Hidden Features & Treasures You Would Never Thought of

The lesson is: There is nothing wrong with adding your brand name into the Subject line but don’t rely much on it. Create your Subject based on your top story or best offer.

5. “Savvy” Grammar

How do you find the Subject lines like this?

“F*ree Shipping Today Only!!!”
“F.REE Health & Beauty Tips For You”
“Download This Web Solution For Your Site – F-R-E-E Instant Demo”

Keep in mind that using the “Free” word in the Subject will not get you blacklisted at major ISP immediately but the attempt to disguise it using a “savvy” grammar can especially if you do other things filters don’t like: broken HTML code, all caps in the Subject, giant font size, excessive colors, etc. 

Even if you don’t intend to fool anti-spam filters, an odd spelling rather confuses the reader than attracts their attention. And many recipients don’t trust much the senders who distort the words in the Subject line.

The lesson is: If you offer something for free, just say “free”. But use the “free” word strategically, don’t just blah-bla to attract the reader. “Free” has a magical power unless you meet it in every other Subject in the Inbox.

6. Hard-to-understand Subjects Lines

“NEW: Sony Ericsson revealed its Vivaz phone – microSD card slot, autofocus, flash, 720p HD recording, GPS, WiFi & More” – hmmm…. yes, the Subject line should tell a lot in a limited space but your recipient doesn’t have to be a tech to understand what you are telling him.

The Subject “NEW: Sony Ericsson announces Vivaz, S60-powered HD capable smartphone” is much better.

The lesson is: Highlight one or two main product features in your Subject and add “& more” at the end to entice the recipient to read the letter. Even if the end is truncated, the Subject will not suffer much.

Conclusion: You will never know what works best for your recipients if you don’t test your email campaigns. 

Test your Subject lines before you send email campaigns using a simple A/B split test. The A/B split test means that you create two or more versions of your email differing by one element (in our case by the Subject line). You send these versions to a part of your list (to 20%, for example). You track email opens to see which version performed best. After you determined the winner version, you send it to the rest of your list.

You can easily do an A/B split test using our G-Lock EasyMail software and G-Lock Analytics email tracking service.

Just download a free version of G-Lock EasyMail and setup a free account on G-Lock Analytics and start testing your Subject lines now.


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