Resources Home

How Long Should Your Email Copy Be?

Published by Jeff Giddens

When it comes to email copy length, people ask us all the time, “How long should my emails be?” I hate to disappoint, but there’s no right answer. Your emails should be long enough to adequately convey the value proposition and to motivate your donor to click and take the intended action.

The real question is “How much copy will it take to get there?”

How email copy length affects click-through rate and donation conversion rate

Experiment #2555

This experiment on email length is a great example of why we need to test our hypotheses. This is an email with our research partner, Chuck Colson Center for Christian Worldviews. As you can see, the initial email is extremely long.

Experiment 2555 - Email Copy Length - Control

If you put this email into a document, it would be three to four pages long. The donation ask is made in the email, and it made a very compelling value proposition. The landing page is short-form and doesn’t have a lot of copy.

We wondered if the email was asking too much. To test our hypothesis, we adjusted the email copy length so that it was shorter. This meant that the landing page copy needed to be lengthened to convey an effective value proposition.

In this treatment, the email is selling the click, and is relying on the landing page to make the actual donation ask.

Experiment 2555 - Email Copy Length - Treatment

The treatment produced a 1,209.2% increase in click-through rate!

Four-digit increases like this get us jumping up and down at our office. We think, “Yes, we’ve cracked the code! We got more people to engage.” If the click through rate was the only email metric we were measuring, we’d be extremely excited. We went from a very low click-through rate to a very high click-through rate, simply by changing the email copy length.

Experiment 2555 - Email Copy Length - Donation Results

But as we’ve seen in other examples, we can’t just look at one metric. We have to look at the downstream metrics as well. The problem with this treatment is that it resulted in a 30% decrease in donations.

This reminds us that the placement and weight of our call-to-action can have a major impact on the motivation of our potential donor.

From the long-form email, we drove very motivated clicks. Since the call-to-action was to give, the people that clicked were already prepared to donate.

From the short-form email, we drove a lot more clicks. But since our call-to-action was a lot lighter, the people who clicked weren’t as highly motivated to donate. As a result, our landing page was unable to influence this less motivated traffic to make a donation.

Key Learning

Clearly, we see that there is a strong relationship between clicks and donations. And the length of your email appeal copy can have a significant impact on both metrics. In order to find the copy length that generates the most revenue, we need to test.

The right length of copy can vary from organization to organization, audience segment to audience segment, and even donor to donor. The only way to know what will work best for your emails is to test.

If you want to find the answer to our original question of “How long should my email copy be?” – write a new email variation, split your traffic, and measure every metric. You may find that your donors behave a lot differently than you expect.

Conveying an effective value proposition

Why Should I Give to You?Finding the right email copy length is all about determining how much copy you need to effectively communicate your value proposition. And most organizations aren’t effectively answering the fundamental value proposition question:

Why should I give to you, rather than some other organization, or not at all?

Grow your conversion rates by learning to answer this fundamental question through this free eBook, Why Should I Give to You?


Published by Jeff Giddens

Jeff Giddens is President of NextAfter.

,,