Measure your email acquisition success

Trendline Interactive

5 minute read

The lifeblood of a high performing email program is growing the email subscriber base, whether by converting current customers into subscribers or attracting new ones. Having a growing subscriber list is an important indicator of a healthy digital marketing program, but the quality of those subscribers is just as important as their quantity.

In this post, we’ll explain why quality matters and how to learn which email acquisition strategies will help you attract the best subscribers for your customer base. (See our previous post, “How to Grow Your Email Marketing List,” for effective opt-in strategies and tactics.)

Why quality matters

Size is important for an effective email database because it means you are reaching a broader share of your market with email. A larger database allows you to segment and target communications to be sure you’re always sending the most relevant messages. It’s also a reliable data source for testing new approaches and understanding what your customers are thinking and doing.

However, size does not equal quality, especially if a large percentage of your database doesn’t open or act on your emails. Higher-quality subscribers–those who actively opted in to your emails and who come closest to being your ideal customer–are more likely to open and click regularly.

You could have 1 million email records in your database. But, if only 250,000 of them have any measurable email activity in the last year or so, the other 750,000 records have far less value. (Note: That doesn’t mean you should drop them from your database. You just need to treat them differently from active subscribers.)

Email acquisition and quality

When you know which acquisition strategies attract the highest-quality subscribers for your brand, you can determine the right strategies and channels to invest in moving forward–where to turn up the heat in one area and turn it down in another.

Tracking behavior is important for measuring quality. Many marketers use end goals, such as purchases or other conversions, to rank subscribers on quality, but other factors can help you measure the success of your acquisition efforts as well.

Who are your ideal customers? No matter how large or mass market your brand is, you should have a picture in your head (age, gender, income, education, geography, marital status and more). It’s more than abstract personas–they’re the customers you want to attract and retain.

This picture must inform your acquisition strategy because it helps you identify lucrative acquisition sources and the tactics that are most effective in capturing the best email addresses.

But how do you know if the person signing up for your email fits your picture of the ideal customer? It’s hard to know when your opt-in process collects only the email address plus one or two other fields (name and location, for example).

Adding more fields to your opt-in form isn’t the answer–the more questions you ask, the less likely people are to complete the form.

You can tease out this information using progressive profiling as part of your onboarding process. But, in the meantime, you can define your ideal customers from a behavioral metrics perspective.

3 critical metrics for subscriber quality

As most marketers know, what customers say they will do and what they actually do are two different things. However, the beauty of email is that you have a variety of metrics at your disposal that can gauge actual behavior, so you can tell if your new subscribers look like a good customer fit for your brand.

To identify what a good subscriber looks like, use a combination of these metrics:

1. Engagement rates

These include positive metrics like open, click-through and conversion rates, and even negative rates like unsubscribe or spam-complaint rates (more on unsubscribing in the next item). These are table-stakes metrics that help you understand what kinds of content motivates your customers to act.

But don’t just look at a metrics report after your campaign concludes. Track whether these metrics are trending up or down message by message. Your email sending platform might do this for you. If not, start a spreadsheet and watch what happens.

Also: don’t stop tracking rates immediately after the campaign is over. Go back and look for residual clicks days or even weeks later. Many subscribers are interested in your brand but will not click on emails until they’re in the market for your product or service. They’ll keep your email in the inbox and will go back to find it when they need it.

2. Unsubscribe rates

The unsubscribe is generally considered a negative metric, but it can generate tons of helpful information and even improve the health of your database. Besides measuring and tracking unsubscribes, look deeper at what your unsubs are telling you.

Unsubscribing happens for many reasons: Some customers unsubscribe because they don’t need your products anymore. Others unsubscribe in order to resubscribe with a new email address (that indicates you need to give them a simpler way to update their records). And, some people unsubscribe because your content doesn’t interest or appeal to them any longer. That’s a strong signal that it’s time for a content or strategy refresh.

But some of your acquisition strategies can also end up driving high unsubscribes. Suppose you offer a 10% discount to new email subscribers. A fair number of them will redeem that discount on a purchase and then unsubscribe. That means your follow-up emails need to work harder to show the value of remaining on your list.

Unsubscribes help you track which acquisition channels or strategies aren’t giving you the customers you want. A co-registration channel that delivers subscribers who routinely opt out right away or never engage will not help you increase subscriber quality, no matter how many records it funnels into your database. That’s why it’s so important to track engagement and quality by acquisition source.

3. Customer lifetime value (CLTV)

This is more complex than tracking engagement metrics because you need time, technology, and models to make it work. However, CLTV has become the No. 1 KPI for measuring success. So, if you aren’t tracking it, you could end up optimizing your emails for customers who don’t generate the revenue you need to meet your business goals.

To measure CLTV, you must be able to measure from first click on the email to last click on a purchase and attribute email’s share of responsibility for that purchase. Then, go a step farther back and see which acquisition sources deliver more customers who end up buying sooner or later.

Why you need both engagement and CLTV metrics

Measuring how well your acquisition strategies bring in the kinds of customers you need to grow your business is essential to help you understand if you’re spending time and money effectively.

As we noted earlier, purchases and other conversions are key success metrics, but they aren’t the only ones. Email can effectively nudge customers into actions that fall outside the purchase cycle, like going directly to a website instead of clicking from the email, or shopping in-store based on an email promotion. Engagement metrics capture that activity, which would be overlooked by conversion metrics like purchase.

Besides engagement and CLTV metrics, you will need another set of measurements to help you understand subscriber quality. In a future post, we’ll explain how hard bounces and spam complaints must factor into your assessments of both acquisition sources and subscriber quality. Stay tuned!

Trendline Interactive

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About the Author(s)

Trendline Interactive

Built from email marketing, Trendline Interactive is an agency and consultancy that inspires brands to create meaningful engagement through cross-channel communications. Our passion is that every single message sent is not only meaningful to the audience, but drives success for our clients.

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