9 Rules We Always Follow When Writing Our Newsletter

newsletter marketing advice

You don’t have to look far to find advice on improving your email marketing in general. However, advice specifically focused on newsletter marketing is harder to find. There is a big difference between targeted ad hoc email promotions and newsletters, just as a magazine subscription and piece of direct mail differ. So trying to apply the advice currently out there on email marketing to your newsletter can be counter productive.

In this article, I describe what I consider to be the 9 most important rules you should follow when publishing a newsletter. Get these right and you should have a newsletter that consistently exceeds industry averages across all key metrics (more about those later).

We’ve decided to put our stats where our mouth is and share the performance data from our monthly Scalable Path newsletter. This includes our actual metrics, over the last 9 months, as well as the industry standards we strive to beat.

Let’s start by defining what an electronic newsletter is. It is a regular communication between the brand and its subscribed audience. A newsletter should strengthen the relationship with subscribers by offering valuable content in a tone that reflects the brand’s core values.

This is unavoidably vague as an email newsletter can be many things. I often find it easier to explain what a newsletter isn’t.

  • It is not an ad-hoc promotional email
  • It is not a method to directly sell a product or service
  • It is not a transactional email based on a user behaviour trigger
  • It is not a serialized email series tailored to sell a product or service

Rule 1: Don’t make false promises

Let’s start here with an often ignored rule. Don’t lie to people. Don’t promise one thing and underdeliver with the content.

Yes. I’m talking about click bait.

Newsletter marketing should be part of a relationship that spans many years. But it will only last that long if you are honest with the other parties in the relationship. Your email subject line is a promise to your reader. By luring them to view your email with misleading prose you are breaking that promise.

This sounds really obvious. It is really obvious. But it’s easy to get carried away when writing your subject line. Always remember you are writing to a person, not just aiming for a high open rate. Thinking of the latter will lead you into click bait territory.

The problem here is that click bait works in that it will get you a higher CTR. But this is short-term thinking and is not a good strategy when building a subscriber base. Once a user clicks through and does not see what they expected, your high open rate will be followed by a higher unsubscribe rate.

“Your subject line and headlines must remain true to your content at every stage.” Head of Digital, Antony Boffey, Radius Solutions.

Now that we have shut that ‘click bait’ door for good, we still need to get people to read our content. At Scalable Path, we spend on average 10 hours researching and writing each blog article. The newsletter is a big traffic driver to these articles so we definitely don’t want a poorly crafted subject line to half the amount of readers we get!

My preferred method for writing subject lines (or headlines) is one I heard from the guys at Hubspot a few years ago. I write 25 versions: not stopping or getting up from my chair until I reach that number. To start with it was excruciating. Sometimes it still is, but it’s a great way to break away from your prescribed style and discover new ideas.

It’s also a sensible idea to have someone on your team look over and sanity checks your final subject line choices. I still get carried away with wanting to run headlines that are on the wrong side of our brand values.

“A great subject line has the power to truly change the success of your campaign.” Olivier Stark, Head of Marketing, Geronimo Mobile

The average Open Rate for our industry, according to Mail Chimp, is just under 20%. Our newsletter currently averages around double that. The chart below shows open rates since July last year.

Newsletter Marketing Subject Line Performance

We get these respectable open rates by responsibly using some well-known psychological principles.

Get to the point quickly

You have both limited time and space to get your message across. So get to the point. You should aim to convey the gist of your message within 5-7 words. This means two things happen:

  • The preview on mobile screens will still make sense
  • The user can decide if they are interested while scanning their emails

Use the active voice

While there are many ways to construct a sentence, often the best way to make them dynamic and succinct is to use the active voice. You can read about active and passive voice here. In the case below, the subject lines in the active voice performed significantly better than the other example.

Newsletter Marketing table showing subject line performance

Ask a relevant question

This is a powerful and honest way to get someone interested. Let’s say you have just written an article on how to be a better Product Owner (here is one we prepared earlier). You could have a subject line that says ‘How to be a great Product Owner’. It is certainly concise. But to turn it into a question makes it more powerful ‘Are you making these product owner mistakes?’ will almost certainly have a better open rate.

Does your subject line generate curiosity or greed?

These are powerful emotional triggers, but they can be used ethically. Consider the difference between the two headlines:

  • Improve your newsletter marketing performance.
  • Are you using these tricks to improve your newsletter performance?

None are spammy but no guesses as to which will perform best.

Does your subject line generate a sense of urgency?

Occasionally you will have an article or offer that is time-sensitive. When you do, using scarcity and urgency in your subject line can really improve performance. According to Hubspot, it can boost your open rates by up to 22%! We sometimes cover events and conferences in our blog and this time-sensitive content is a great opportunity to apply these principles. Use merge tags when possible and appropriate. Merge tags are an effective way to customize content to each recipient. Typically the variables used are ‘name’ or ‘interest’ but could, depending on how you collect data, be anything: from Age to Zip.

In the Scalable Path newsletter, we currently just use first name (in the subject line and email body) to make the messaging more personal. Even this common use of mail merge tags increased when tested, our open rates significantly.

Use numbers

I’m sure you have noticed this established trend of putting numbers into subject lines.

  • 10 tips..
  • 9 ways…
  • 8 best…
  • 7 steps

Numbers are powerful psychological influencers. You can make a 1 month trial sound longer by calling it a 30 day trial for example. Many subject lines use numbers to give an article a sense of both purpose and brevity. This often improves the open and click rates.

Rule 2: Use a good template design

The debate between plain text emails and HTML emails is interesting. The issue lies with research that consistently shows that plain text emails outperform HTML emails. The reasons behind the poor performance of this more visually pleasing format are often associated with a mix of poor coding and inconsistent rendering by mail clients. But there is a third reason that likely affects the poor performance of the HTML format: too much noise. Adding a bunch of photos, columns and other visual elements can, if not well thought out, dilute your main call to action (CTA).

Should you just keep your plain text newsletter? I don’t think so.

Your goals when building a newsletter are more nuanced and long-term than in a promotional mailshot. You need to consider the relationship you are building. A consistent visual identity is critical to this goal.

Creating a Template

You have three choices when it comes to templates: use a pre-built template, customize an existing template or develop your own from scratch. Sites like Envato and ThemeForest sell some very well designed templates. Many email marketing platforms, like MailChimp, also let you use their templates at no extra charge.

Last year we decided we required a new look for our newsletter. Our old template was clear, concise and performed well. But it did not correctly represent Scalable Path’s new visual identity. So we set out to design a new template that would look great – but not negatively affect performance.

One of the key considerations for this template was to ensure it rendered correctly on mobile devices. Recent research shows that almost half of people check their email primarily from a mobile device.

Initially, we tried to design a responsive template but found, when testing, that this rendered poorly on many devices. We eventually found the best compromise was a newsletter with a fixed column width of 600 pixels.

Because of the vast number of email clients out there, each of whom renders HTML differently, developing a template can feel like an uphill battle. We decided to develop for the largest email clients. By doing this you can cover 91% of the market with just a handful of clients!

  • Apple iPhone, iPad and Desktop with 51% market share
  • Gmail and Google Android with 29% market share
  • Microsoft Outlook and Outlook Live with 11%

Litmus has a great set of emulators that covers remaining email clients – from mobile to desktop. But beware, I have found that the emulators do not always accurately depict the end result. I suggest you actually test on multiple devices: like iOS and Android.

Rule 3: Frequency is everything

There are a lot of opinions out there about the best time of day and day of the week to send your email out. This will have an impact for sure, but not a massive one. As long as you send your email on a weekday there are only a couple of percentage points in it.

Performance of emails by day of week

The rules around timing are pretty simple: – Send Monday to Thursday – Send during audience office hours

What is less obvious is how frequently you should send your newsletter. Be it: daily, weekly, monthly or something in between.

There are some articles out there that will recommend the optimal frequency. Ignore them.

Frequency is unique to your situation. This is because it depends on one thing: how much valuable content can you write. That is the question we asked ourselves before we decided on a ‘once a month’ frequency for the Scalable Path newsletter.

Initially, we wanted to publish more frequently. We have a network of thousands of world class freelancers. Surely we could generate an article a week, right?

Well, we could, but the quality dropped. The thing about great developers and designers is that they are busy doing the work they love. They are not necessarily interested in writing great content. To achieve our goal of unique, well thought out and original content we had to limit ourselves to one article a month.

Go through this thought process yourself. If you cannot produce great content, you should not bother producing any. Your newsletter, at its core, is driven by content. And in a world that is drowning in content already, yours needs to be good.

Rule 4: Create a content calendar

A content calendar is simply a way to plan how your content will be distributed throughout the year. Planning ahead gives you an opportunity to balance your content out. In our case, we alternate between themes like programming, project management, and marketing.

We try and keep our calendar full around 6 months ahead and always have one finished article in the queue – just in case something happens to our content pipeline.

I have found that, in this industry at least, if I plan more than 6 months ahead, the content tends to become less relevant to users. Writing within a 6 month window gives the option to spot trends coming in and write about them.

NB: We currently use task management software to manage our content calendar, but you equally use a spreadsheet.

Rule 5: Not all metrics are created equal

Do some research on email metrics and you will see reams of articles with titles like ‘Top 20 metrics you need to track on your newsletter’.

You can spend your time better than analyzing 20 metrics! I would say you should be keeping a close eye on no more than 3 metrics: the conversion rate of your newsletter and the metrics that directly feed into it.

Conversion Rate

To start with, your newsletter will likely have a specific goal. Often it is to drive sales or registrations, but it could equally be about moving traffic to your website. Just be sure you decide what this end goal metric is and make sure you are tracking it in your analytics.

The conversion rate is the ‘key’ metric and ultimately what I focus on long term. If the trend is up, I’ll sleep well at night. The conversion rate is the percentage of recipients who clicked through from our email and completed a lead form.

Click Through Rate

This is the percentage of recipients who clicked on any of the links within the newsletter. I tend to think of this as a measure of user engagement. A good CTR shows me that the article and copy were well chosen. If the numbers drop then I know I am losing the audience and will work out how to address the issue. Often by changing the content mix.

Open Rate

This is the percentage of recipients who open your email and view it. I consider this a vital metric but it’s important to understand it is flawed in a few ways. Factors such as blocked images, preview panes and non-HTML clients affect the accuracy of this metric. However these are pretty consistent, so you can track changes confidently. Just don’t put much weight on the reported number.

You may have noticed there is no mention of the unsubscribe rate. This is because I don’t feel this is a reliable picture of the health of an email list. Many subscribers won’t use the unsubscribe process. They’ll just stop opening, reading, and clicking on your email messages. It’s much more effective to measure indicators of engagement (like CTR) to gauge how well you are doing.

Rule 6: Greymail is the new black

If you haven’t heard of greymail yet, prepare to be unhappily surprised.

Remember that time you wanted that great new marketing eBook, but you needed to subscribe to the author’s website to get the download link? Greymail is an email that you, at one point, opted to receive, but probably never wanted and don’t engage with.

Your mail provider is able to track this (lack of) engagement. The difference is now they have decided to act upon it. Google really led the way with this but Microsoft Live (Hotmail) followed suit. In a grossly simplified manner, they monitor engagement, across the board, for every vendor. In other words, if your list has a low engagement rate your emails will likely be filtered to a secondary inbox (like Gmail’s Promotions Inbox) and never be seen. Or at least not in a timely manner.

There are two ways you can directly lower the chances of your email ending up as Graymail.

  • Make your Unsubscribe process clear and effortless. If someone wants to unsubscribe let them. Don’t harm your brand with a convoluted process designed to confuse them or by creating 10 lists and only unsubscribing them from one.
  • Graymail penalizes poor email marketing for the most part. But, even the best marketing newsletters have their share of unengaged users. The solution? Ditch them.

If these people are not engaging and have a history of no engagement then they are bringing nothing to the table and now may actually be harming your performance. This seems a little counter-intuitive, but it’s key if you want to maintain an active, engaged subscriber list. Don’t use weird language like “Alter your communication with us.” Don’t hide an unsubscribe button behind an image without alt text. Besides keeping your list healthy, having a clear unsubscribe process will help ensure your email isn’t marked as SPAM before it hits the rest of your list’s inbox.

Rule 7: Split testing

I would like to split test much more than I actually do. But the reality is that, while valuable, testing is time-consuming.

Split testing (which is also referred to as A/B testing or multivariate testing if someone is showing off) is a method of conducting controlled, randomized experiments with the goal of improving a particular metric.

The variables tested in these experiments can vary even more wildly and are certainly not limited to the subject line.

Let’s consider an example: you redesigned your website recently and want to update the look of the newsletter template to better match this new design. Keeping the content of the upcoming newsletter the same, you could create a split test using the old template and the new template. The results of this test will show you any performance changes are directly related to the design. If you were to just send a newsletter out with the new design and then compare performance to last month, you would not be able to isolate the change in performance from other variables such as content, subject line etc.

Mailchimp, which is the email marketing platform we use, has limited but easy to use testing capabilities built in. You don’t have to be a statistics whiz to get started. Most other popular platforms have similar functionality.

What’s great about split testing with email is the ability to stagger delivery in order to use better performing variables on a larger chunk of your audience. For example, I use the subject line testing for virtually every issue. I will send different test subjects to a subset of our subscribers initially, then Mailchimp analyzes the results of that test and push the best performing subject line to the rest of the subscribers.

Rule 8: Segmentation

We don’t currently segment our newsletter, so why am I placing it on a list of essential rules? Because you should at least consider a segmentation strategy. It is common knowledge that segmentation and performance are positively correlated. Want the highlights? Segmented emails get 14% more opens and 57% more clicks. Segmentation can have a massive impact!

Let me illustrate how vital sensible segmentation can be with something I’ve been considering setting up for a while.

As the Scalable Path business has grown the audience has changed slightly. As a result of these changes, our audience can now be split into several broadly defined interest groups: development, design and marketing.

Segmenting into these same groups would bring some benefits and some negatives.


  • I would be able to show more relevant content to correct subgroups. Are all developers interested in marketing? No of course not, so sending them a marketing article, followed by a design article could make them lose interest with the newsletter.


  • More content will need to be created. Which brings us back to Rule 3: Frequency is Everything. I would need to be confident I could produce 3 times more content at the same level of quality.
  • We grow our list from multiple feed points and not all can be easily adapted to accommodate this new segmentation strategy

Rule 9: Use a checklist

I really can’t stress this point enough. Create an in-depth checklist and work through it attentively before you send every issue out.

I actually have 2 checklists, one for the blog article and one for the newsletter. Before I go and publish either, I run through each checklist methodically and check off all 50 points! I cannot tell you a number of silly little errors that occurred before I adopted this rigid system. From incorrect merge tags to broken links.

And Finally

Newsletters can be a vital part of your marketing arsenal when used correctly. They can drive sales, increase loyalty or bring people back into your funnel. But if not correctly managed they can easily go astray becoming a liability on your resources.

Hopefully, this newsletter marketing article has given you an idea of areas you may be neglecting in the management of your own newsletter.