fly icon
Brainery | | Email Marketing: Your Definitive Guide to List Building

Email Marketing: Your Definitive Guide to List Building

Email Marketing: Your Definitive Guide to List Building - Replyco

The ultimate resource for getting the most out of your list building campaigns, featuring expert insights from the email marketing pros at Litmus.

Contrary to popular belief, email marketing is nowhere near obsolete. In fact, your email list building and marketing strategies are as important to business growth and profitability as they’ve ever been (if not more so). 

That’s because, despite the rise of social media and other communication channels, email still reigns supreme. Studies show that 99% of consumers check their email each and every day. And with work accounts, personal email addresses, smartphones, laptops and the like, many people open their inboxes 20 times or more within any given 24-hour period.

So how do you take advantage of such a wide and readily available audience for your brand’s messaging? How do you attract the right demographic, get them to subscribe to emails from your company and keep them engaged? 

In a recent conversation with Litmus Director of Content Marketing Megan Moller and Email Marketing Manager Jaina Mistry, Replyco got the answers to these questions and more. From the Litmus team’s expert insights to our in-depth industry research, we’ve compiled your definitive guide to email marketing and list building. Keep reading to learn everything you need to know about how to drive your audience numbers “up and to the right.”


email opt-in tips - Replyco Helpdesk Software for eCommerce

Let’s begin this guide by taking a look at opt-in tips and best practices. From making sure you’re compliant to figuring out where to find your audience and how to attract them, there are a few steps you need to follow in order to achieve the best results.  

Understand Compliance Rules

According to the dynamic duo at Litmus, the first step in any email list building campaign should be to familiarize yourself with compliance and security requirements. They advise, “Familiarize yourself with compliance (like GDPR, CAN-SPAM and more) and security requirements for your organization and where your target audience resides. Different countries — and even states — have different laws.”

Document & Plan Your Process

Litmus also says it’s important to understand and document your opt-in process before beginning your list building campaign. This doesn’t have to be complicated, but it’s a crucial step in planning out your strategy. 

What kinds of opt-in forms are you using? What type of information do you want to collect? Where will you be placing your opt-in content? These are all questions you need to answer when putting together your process.

While prepping, you also need to lay out an email workflow before you start collecting sign ups. For instance, you’ll need a “thank you” or “welcome” email that goes out immediately when someone opts in. 

Whatever your plans, document the entire workflow and process, including steps, strategies and goals. Not only will this make executing your opt-in strategy more seamless, it will also help you measure campaign effectiveness and success later.

Use Lead Magnets

Now comes the fun part: attracting your audience. A great way to encourage more opt-ins is to use lead magnets. These are exactly what they sound like, pieces of content or incentives that attract leads by offering them something for signing up. 

One example of a commonly used lead magnet in retail is free shipping in exchange for providing an email address. Other offers include order discounts, complimentary items and free trials. 

Depending on what you specialize in, you can also use premium content to incentivize users to opt in. For example, Replyco recently provided a comprehensive set of “20 email templates for eCommerce sellers” to new registrants. Just a few additional types of premium content that tend to attract customers are eBooks, guides, webinars, podcasts and cheat sheets.

Whatever lead magnets you choose to offer, make sure they’re of value to your audience. Not only will this help to increase opt-ins, it will also go a long way toward improving your brand’s reputation as a thought leader in your industry.

Find Your Audience & Attract Them with Great Content

According to Litmus, “Your email program is only as good as the content within it. Building a strong content program — even if it’s one or two ‘magnet’ pieces — can transform not only email performance, but also how many you attract to sign up for your list, and your content!”

In explaining how to attract your target audience, they go on to say, “Are there communities with good reputations where your future subscribers can be found? Getting these content magnets in front of those audiences through syndication or sponsorship can be key to driving your audience numbers up and to the right.”

Utilize Social Media & Paid Ads

When it comes to list building, don’t limit your reach to just an opt-in page on your website. While those are important, you also need to utilize every channel you can in order to increase your brand’s reach. 

The team at Litmus says, “Look to other [verticals] to help promote your email channel. Can you use social media or paid ads to grow your audience?”

Implementing a list building strategy that includes social media, paid ads and the like can help you target consumers who are searching for and talking about things that are directly relevant to your brand. Plus, you can post about events and promotions on your social channels without spending a dime. 

Publish Landing Pages & Pop-Up Forms

Two other great ways to collect sign-ups are landing pages and pop-up forms

Landing pages are pieces of marketing content that revolve around a specific topic and encourage a specific action — in this case, signing up for email updates from your company. 

When creating a landing page, make sure the content is simple, straightforward and easy to read. Display any call-to-action buttons prominently (preferably at least once in the top half of the page and once at the bottom), and set them to lead to your email opt-in page. 

The design of your landing page should be eye-catching, with plenty of relevant imagery and a scannable layout, but without being too “busy.” 

Pop-up forms often get a bad rep for being annoying or intrusive, however, they can be incredibly useful for gathering site visitor information. Just make sure they aren’t set to pop up too often, and also ensure they appear at relevant times. For instance, if you run an email marketing company and are offering a page of templates in exchange for opt-ins, set your pop-up form to appear when users open a page on your website that is relevant to templates.

Discover & Test Entry Points

When building your list, it’s important to keep up with what’s working and what’s not. 

The duo at Litmus says, “Discover where all your subscription entry points are and dig into which ones are the most effective and in line with your business goals. Optimize this process through testing (hint: testing doesn’t have to be complicated), so that any campaigns you run will have the highest chance for success.”

And as they said, testing doesn’t have to be complicated. This is just a matter of determining which entry points or collection methods are netting the most opt-ins, and which ones are underperforming. Once you have this information, you can adjust your strategy accordingly.

Email Marketing Content + List Nurturing

Content + List Nurturing - Email Marketing: Your Definitive Guide to List Building - Replyco

Getting people to sign up to your email list won’t get you anywhere if you can’t keep them signed up and engaged. Let’s take a look at, perhaps, the most important pieces of any email marketing strategy. 

Provide Value to Subscribers

First and foremost, your email content should be valuable to subscribers. After all, most of us receive hundreds of emails every single day. And many consumers report a belief that they receive too many marketing emails already. Make sure anything you send to your list has a purpose and cuts through the white noise. 

This means all of your communications should be engaging and full of useful content, whether they’re newsletters, sales promotions or event announcements. 

Create Share-Worthy Content

In addition to high quality, you also want to make sure your content is share-worthy. If it is, your current users may become your most effective brand ambassadors. 

When it’s interesting enough, anything you send to your existing list could potentially get you more subscribers. That’s where value comes back into play. And be sure to include social sharing buttons in every piece of communication. That way, in addition to forwarding, your subscribers can also share via social media. 

Include Your Audience

We all want to feel included. That’s why subject lines containing words like “you” and “your” tend to perform so well in open rate metrics. 

When it comes to emails, Megan and Jaina at Litmus advise, “Include your customer in your content. Running polls, creating surveys and sharing those results / insights with your audience shows you’re listening to them and gives them info they want. It provides a way for you to put data around trends and how they apply to your solution.”

This sort of inclusion can also help you improve other facets of your business. For example, in almost every email from Replyco, we invite subscribers to visit our Public Roadmap. This is a page where users can view information on new and upcoming feature releases, submit their own requests and vote for their favorites. The feedback we receive has been integral to our growth as a customer-centric software company, and plenty of the submissions have come from people who clicked the Public Roadmap link in an email. 

Make Your Content Easy to Read

We’ve all opened an email only to find a long, unending paragraph of boring text that caused us to click away (or worse, unsubscribe). That’s why the layout of your emails is every bit as important as the content itself. 

Litmus recommends, “Make things skimmable and accessible. When you look at your email, if someone only sees the headline, image and call-to-action (CTA), does it tell your story for you? And what you want to get across? Quality assure (QA) your emails with all of your audience in mind. 6% of Americans have some form of visual impairment. Optimize your alt text and use a screen reader if you can.”

Summed up, upon opening an email from you, readers should be able to estimate what the content is about simply by scanning the headlines, imagery and CTA. Make sure the text is large enough to be read easily and that the images are crisp and clear. 

Assess Campaigns for Effectiveness

Here’s a really big one. In addition to evaluating your opt-in processes to determine what is and isn’t working, you also need to do the same for your email campaigns.

According to Litmus, “List building is as much about maintaining your current list as it is growing your list. Look at your current email program and identify any email campaigns that are driving unsubscribes or are particularly unengaging. Start with optimizing those campaigns.”

They go on to say, “On the flipside, identify your most engaging email campaigns, too. Dig into the metrics to understand why they’re the most engaging — is it the content, timing or audience? Can this be replicated across other campaigns?”

Protect Against List Deterioration

While focusing on gaining new subscribers, make sure you aren’t losing existing ones. 

It is true that some amount of list deterioration is unavoidable, such as when people change email addresses, use a company email address to sign up and then leave that company or simply use a dummy email account to opt in. That’s part of the reason why you need to always be adding new subscribers.

However, you should pay very close attention to your list numbers so that you will know if and when unsubscribes spike. Which leads us to the following important component of any email marketing strategy…  


This isn’t the first time we’ve mentioned testing in this guide, and it won’t be the last. Testing is absolutely critical to making sure you’re deploying the best strategies possible for your email marketing and list building campaigns. Otherwise, if you’re not continually checking in to see what works and what doesn’t, you’re essentially wasting a tremendous amount of time and effort. 

Here’s what Litmus has to say on the subject: “Test, test, test! While benchmarks are great to get some guidance on what you should be doing, knowing what resonates with and engages your audience most will only come from testing.”

Litmus once again stresses the fact that tests don’t have to be difficult or complex, saying, “Tests don’t have to be complicated. Whether it’s testing subject lines or the format of your emails, you can run tests quickly and learn from them. We share results from some tests we recently ran here.”

List Building Pitfalls

2 List Building Pitfalls to Avoid - Email Marketing: Your Definitive Guide to List Building - Replyco

We’ve covered a bit about the pitfalls to watch out for in your email marketing and list building strategies, such as unsubscribes and boring content. However, let’s dive a little deeper into two of the most commonly made mistakes and how to avoid them.

Inadequate QA Process

According to the marketing pros at Litmus, your quality assurance protocol can make or break your email list building efforts. 

When we asked what pitfalls email marketers should avoid, Litmus’ first answer was, “Skipping or not having a thorough QA process pre-send.”

They went on to say, “Mistakes or broken emails can lead to sub-par subscriber experiences and put your brand image at risk.”

Poor List Hygiene

The next common mistake, according to Litmus, is not keeping up with “list hygiene.” We touched on this previously in the “Protect Against List Deterioration” section, but here’s what the Litmus team had to say on how marketers can mitigate the issue:

You can tackle this through re-engagement campaigns to try and reactivate subscribers, but there is also something known as sunsetting subscribers. This means, you no longer email them after a certain period of non-engagement or other metric that aligns with your business. You can also ONLY email them for certain things like product releases in an effort to win them back.”

Email Marketing & List Building Bonus Tips

Bonus Tips - Email Marketing: Your Definitive Guide to List Building - Replyco


We also asked Litmus’ dynamic duo Megan Moller and Jaina Mistry about any bonus tips they would like to share. They had plenty more insights… 

Go Beyond Traditional Metrics

First of all, the Litmus team says to go beyond traditional metrics to determine how best to attract and interact with your audience.

“Go beyond traditional email metrics. Understanding standard email performance like deliverability, open and click-through rates is important, but also understanding things like email client usage and which devices your audience is opening emails on is just as important, if not more so when it comes to design. For example, if the majority of your audience is opening up emails on Apple iPhone, you should probably weave a Dark Mode strategy into your program. We just released some very early data in our State of Email Engagement report showing that 36% of Apple iPhone users are using Dark Mode.”

Don’t Buy Lists

And like so many in the email marketing game, Litmus also cautions strongly against buying lists. 

“Do not buy lists! While they may seem like a great idea to increase your audience size, there are a lot of pitfalls that come with mailing to a purchased list. In fact, most reputable email service providers (ESPs) or marketing automation platforms (MAPs) don’t even allow you to actually send to a purchased list. Plus, performance and user experience in these situations tend to be poor and not give you the return you’re typically looking for.”

Apply What You Learn to Other Areas of Your Business

Your email list is essentially the same exact demographic as your sales prospects. So anything you learn when planning, implementing and testing email marketing campaigns can apply to several other facets of your business.

Litmus says, “Apply what you learn in email to other channels. You have a built-in focus group in your email list that is exactly like the audience you’re trying to attract. Listen to what they are saying. If a headline works in email, it will likely work in social or ads.”

Do What Works for You

And while it’s important to adhere to compliance regulations, there are no other concrete rules for email marketing and list building. You should do what works best for your business and create the content that resonates most with your audience. You can also consult what’s performing well for your competitors or research the metrics in your specific industry.

According to Litmus, “There are no hard and fast rules here, except when it comes to compliance and security. Your email program and audience are different from another email program. Look to benchmarks and other programs for ideas.”

Test, and Test Again

Finally, the team at Litmus says, “We’d be remiss if we didn’t say to ‘Test!’ again. It’s that important.”

You can’t possibly know how to move forward with your email marketing efforts, how best to encourage new opt-ins or what to change if you’re not testing the effectiveness of your campaigns. You need to test every single facet you possibly can, including, but not limited to:

  • The performance of opt-in pages / forms on every channel you’re using.
  • Which CTAs are doing the best.
  • Subject line open rates.
  • Email click-through rates.
  • Unsubscribes.
  • Which parts of your emails are getting clicked the most / least.
  • Bounce rates.
  • Deliverability metrics.
  • Landing page conversions.
  • Anything else you can test.

About Litmus

Litmus helps companies get more from their entire marketing mix by “putting the most dependable channel, email, first.” More than 700,000 users across industries, including 80% of the Fortune 100, rely on their solutions to test, analyze and improve email marketing efforts. It’s how they help companies break through the advertising noise to be heard — and get more from email than they ever thought possible.

You can learn more about Litmus’ story and solutions here

Special Thanks

Many thanks again to Litmus Director of Content Marketing Megan Moller and Email Marketing Manager Jaina Mistry for taking the time to provide such valuable insights for this guide. 

Get Control of Your Inbox with Replyco

Here at Replyco, we fully recognize the important role email plays in the sales, marketing and customer service world. As a customer support company first, software company second, we see each and every day just how many consumers utilize email to ask questions and get in contact with businesses.

Our robust platform of integrations and tools enables eCommerce sellers to centralize messages across selling channels and platforms — while reducing response rates, delighting shoppers and boosting ROI. If you’re ready to get your inbox under control, click here to start your no-risk, no-credit-card-required, 7-day free trial today

Want to learn more? Feel free to take a tour of our features any time! Or visit our Public Roadmap to see what’s on tap for the near future, submit your own feature requests or vote for your favorites.

Sheena Ingle - Content Writer for Replyco eCommerce

About the author: Sheena Ingle

Sheena Ingle is a copywriter and marketer with more than 10 years of experience. She studied communications at Southern New Hampshire University and specializes in educating consumers in the eCommerce, technology, customer service and SaaS industries. Sheena's work has been published in major outlets such as USA Today and, and she truly enjoys helping SMBs and online sellers achieve their goals.

To inquire about guest blog posting and other media opportunities, contact Sheena at You can also follow her on LinkedIn.


You may also like

What eBay Star Colors Mean + How to Improve Yours - Replyco Helpdesk Software for eCommerce

What eBay Star Colors Mean + How to Improve Yours

From yellow to silver shooting stars, learn what all of those eBay star colors mean. Plus, find ways to improve your own star ranking as a seller.

Customer service

32 Customer Service Facts You Can’t Afford to Ignore

Your customer service affects everything from profits to employee retention. Here are 32 customer service facts and stats that you can’t afford to ignore.

eBay’s Policy

Navigating eBay’s Policy Against Contact Information in Messages

eBay sellers who include prohibited info in messages experience send errors and worse. Learn how to navigate this policy to keep your account running smoothly.