How to Write Killer Email Subject Lines

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About the post.

I’ve been email marketing for several years now. Whether it’s building up lists for CPA campaigns, collecting opt-ins for eBooks and courses I’ve written, or simply emailing people from my forums or blogs, I’ve sent millions and millions of emails.

Email is still BY FAR the BEST way to build a list.

Yes, there are lots of other ways like retargeting, building Facebook pages and other social methods, but you only ever have full control over your list when it’s email. Email is still the only and best way to directly send someone a message to their inbox.

Hell, I’m sure 90% of people reading this post came from my email, right?

So today, we’re going to look into one aspect of email that is possibly the most important: The Subject Line.

The subject line is basically the “title” of the email that you send to someone on your list. It’s the first thing they see in their inbox and pretty much dictates whether or not that person will even open the email and continue to read it in full. If you have a good subject line, you have a good email open rate. If it’s a bad subject line, you may not even make it into their inbox.

Let’s first start by looking at some quick tips and practices for writing good email subject lines:

Keep It Short

Most users will decide if they want to open your email simply from the subject line, so keep it short so that they don’t have to think too much about their decision to open. If they have to decipher your subject, you’ve lost them. Anything under 30-40 characters will do it.

Example: Check out this new blog post!

Get Personal

If you’re using something like AWeber, you have the ability to embed the name of the email recipient in the subject line. Everyone loves to hear their own name, especially when it’s on an email to them. It gives the user a feeling of rapport and increases opens.

Example: John Doe, Check out this new blog post!

Use Urgency

Using urgency in your subject lines works. Using for example “today” or “ends in 24 hours” will give the user the urgency they need to open the email to find out what they can get today or what is ending in 24 hours. It will encourage them to act now instead of leaving it until later.

Example: John Doe, you have 24 hours to check out this new blog post!

Get Controversial

As you will see below, using controversial subject lines really increases the rates of opens. People love to hear about controversy or something that’s not the norm. Think about it, most people get tens of emails a day selling something. Try coming from another angle to stand out.

Example: John Doe, super affiliates are MAD, you have 24 hours to see why!

Use Benefits

Telling the user HOW opening this email will benefit your open rates also. For example, be sure to tell them exactly what they will get or receive when opening the email. Using exact figures and numbers or percentages also helps here.

Example: John Doe, super affiliates are MAD, you have 24 hours to see why it will make you money!

There are a lot more tips, but really the best thing you can do is start building your lists and recording results. For example, let’s look at some results from just one of my many lists. This is the list I’ve built up over the past few years for the Newbie411 eBook. I’m not going to go into how to build lists in this post, but I’ve been driving traffic to my opt-in page here for the past several years and then emailing the list most weeks with affiliate marketing related updates and products.

When it comes to emailing, there’s only one email marketing software I advise you to use and that’s AWeber. I’ve personally tested Mailchimp, Getresponse and several of the other players in the market, and AWeber is by far the best for several reasons including:

    • 24/7 customer support
    • Price for subscribers
    • Visual email creation editor
    • Split testing capabilities
    • Friendliness to affiliates

Basically, it’s by far the best you can get for your autoresponders and list building capabilities overall. Here’s just a quick snapshot of one of my current lists on AWeber, just so you can see I’m a higher tier paying client:


If you want to join AWeber, you can take advantage of this $1 trial by clicking here.

So, let’s take a look at some of my subject line results.


Let me start by saying this isn’t the most active list on my account. I don’t email this list newsletters, etc. to keep them fully engaged, so although the above isn’t amazing as far as % of opens, it’s very interesting to analyse what does get them to open.

Closing Down…… 17.6%

You can see how the highest open rate was something so simple yet very controversial and intriguing. I tested the same subject line on a much bigger list I have on AWeber with very similar results. The best thing is this email was sent for a promotion we ran, which WAS closing down that day, so we saw a lot of opens and then a lot of clicks and panic buys on the promotion.

Another two in the top six are also using the controversial theme.

Why I HATE LukePeerFly 15.4%
hahaha, super affiliates are mad 13.6%

The LukePeerFly one was a great email that we saw lots of results on. Everyone wants to read controversial emails. A great tip is to publicly call out or diss someone well known like Luke within your own industry. Of course the email went on to basically explain how I don’t hate him but actually love him and showed my email list an interview we did together on his blog.

I pay YOU to join The Dojo 16.0%

Is the perfect example of keeping it short and showing how the email will benefit the user. Telling them that I will pay THEM to join my private affiliate forum The Dojo not only resulted in a good open rate but also had an influx of my email readers joining The Dojo to use our affiliate program and gain commissions.

One tip when it comes to using AWeber to send your emails is to create a split test on a small portion of your list in order to split test your subject lines. You can basically segment a few %’s of your list to send your email to with different subject lines and therefore record the result of the most opened email, which will then be sent to the remainder of your list. I now do this with every email I send to ensure I get the best open rates.

You can do it by simply following these steps:

Step One:
Navigate to:


Step Two:
Create at least 3 emails to test.

  • Email 1 to test subject line 1
  • Email 2 to test subject line 2
  • Email 3 to send the winning subject line

I usually do 4 emails and split test 3 subject lines to 3% of my list and then send the winning email to the remaining 91%.


Step Three:
Create your emails, they should have the same body but different subject lines, leave the large lists subject line blank as we will edit with the winning line from the split test.


Step Four:
Make sure you’re broadcasts/messages are ready and weighted correctly for the split test.


Step Five:
Send out your smaller split test email by selecting the send now option but making sure you select the “send to segment” and select your split test you previously created.


Step Six:
Record your result, send the winning subject line to the remainder of your list.

What are the best subject lines and practices you use for email? (comment below)