How to Increase Email Open Rates: 13 Key Success Factors with Examples

By Andy Crestodina

Visit any major blog and you’ll see email signup forms pop up, slide in and drop down. You’ll see them right when you land and right as you’re leaving.

Why so pushy?

Because email is special. In social media, organic reach is low. In search, clickthrough rates are in decline. For those traffic sources, Big Tech is standing between you and your potential visitor. And they’re not in business to send you free website traffic.

But email marketing is disintermediation. There is no giant, digital monopoly between you and your audience. Once they share their email address, you have permission to contact them directly.

So step one is to grow your list, which means using a high-converting email signup box. One that has the three P’s.

And then comes step two, sending email that gets opened. That’s what this guide is about: how to increase email open rates. We’ll share 13 key success factors in email open rates.

This little diagram will quickly show you where some of our tips are headed. Here’s what it looks like inside your subscribers’ mobile inbox.

You can instantly see how little information the subscriber has while deciding whether or not to open and how much difference the sender name, subject line and preheader text can make.

We have also included insights from some of the world’s best marketers. Seriously, the tips below are from true email experts.

1. Use a human sender name

It’s the most prominent part of the email preview, so it’s a huge factor in open rates. Email marketers may forget to check it, but recipients never forget to look.

If the sender name includes a person’s name, the email is more personal and more likely to be opened. For example, an email from “Susan Clark from Zippy Ideas” will have a higher open rate than an email from “Zippy Ideas Company.”

If you’re human, you have an advantage. It’s easy to delete (and unsubscribe) from messages that come from a company. But when the message comes from a person, that’s different.

We asked Ann Handley to share her best email advice and this was at the top of her list.

Ann Handley MarketingProfs

Your From line matters more than your Subject line.

Why? Your email will be opened (or not) based on your offer (in direct response email) or the promise of value (in an email newsletter).

In either case, the relationship and trust between the subscriber and the brand is what triggers an open more than anything else.

There are a *TON* of tools that help you optimize your Subject Line. There’s no shortcut to optimizing a From line… that’s all on you and the value you provide.

We love this, Ann! Optimize your From line with each and every email by building your reputation for adding value.

This was also one of the top three tips from email expert, Joanna Wiebe.

Joanna Wiebe Copyhackers

“Be really conscious of your From name as, on mobile, it’s got way more visual prominence than your subject line does.”

We’ve seen clients get a huge lift in results from this approach. One client saw their open rates double.

The sender name is easy to change from within your email service provider. Your ESP may even make it easy to A/B test different sender names. You’ll quickly discover if a more human sender name affects open rates.

The next biggest factor in open rates is the subject line.

2. Use a sentence case subject line

After the sender name, your subject line is your next most important way to increase open rates. Let’s start with capitalization. You have two choices:

  1. Title case (“Top Factors in Email Open Rates”)
  2. Sentence case (“Top factors in email open rates”)

We recommend sentence case. This is the first of the three rules of email subject lines from Peep Laja (that’s pronounced “Pep Laya” if you aren’t familiar).

Peep Laja CXL

“Always use sentence case. Better comprehension and reading speed. Your friends would never use a title case when emailing you.”

It makes sense. You’re a person sending email to other people. So make the message feel like it’s from a person with a sentence case subject line. It’s another subtle way to humanize your email marketing.

3. Keep the subject line short (7 – 9 words at most)

Here’s the second of Peep’s three rules: “Keep it short. Real emails from friends never have long subjects. Often they’re a single word. Also mobile Gmail only can fit so much.”

I get Peep’s emails. He does often write single word subject lines. I always open them.

He makes two excellent points. Friends don’t write super long subject lines to each other. And long subject lines get truncated in the mobile inbox of their email client.

Mobile Gmail on portrait view may show just 30-40 characters. MailChimp recommends a maximum of nine words and 60 characters.

Years ago, Mike Madden of Marketo analyzed hundreds of thousands of emails and found short works a bit better. Seven word headlines performed best. In his dataset, the average seven word headline had 41 characters, but who’s counting!

source: Mike Madden, Marketo/Adobe

4. Front load the subject line with the most impactful words

If you do write a longer headline, make sure the most impactful words are at the beginning.

Screens are small and mobile inboxes are cramped. Those first few words might be all that your subscriber sees. So be sure to get the important words and phrases into the beginning of your email subject line.

5. Use numbers, odd or even

Numerals stand out against letters in lines of text. Unless they’re spelled out with letters, numbers improve the visual prominence of your subject line. Those numeric characters can make your email stand out a bit more in the email recipient’s inbox.

And odd numbers seem to work best, right? Everyone says so …but I’ve never seen the evidence. If you assume a correlation between subject lines and social posts, and use social engagement rates as a proxy for email open rates, then social media research may be helpful.

That research doesn’t suggest that odd numbers are any better than even numbers.

Why do numbers work well in subject lines?

Beyond adding visual prominence, when the number indicates that the content is a list, it tells the recipient that it will be easy to scan. It makes the email sound like it will be easy to quickly get value from.

6. Use the top performing words

Your subject line is your hook. If it doesn’t indicate a strong benefit or trigger curiosity, it’s not doing its job.

Some words work better than others. Here’s a selection of words that appeared in top-performing subject line words, according to the analysis of 48 billion emails by four different marketing research companies:

Sources: Marketing Profs, ClickZ, Smart Insights, Digital Marketer

Keep in mind, your subject line doesn’t have to be the same as the headline of the article. Subject lines have nothing to do with SEO, so there’s no need to include a target keyphrase.

Subject lines are strictly about empathy and psychology. Be unexpected, helpful, provocative—or all three. So tailor it specifically for the inbox. In fact, you should tailor every type of headline (title tags, H1 headers, social posts, subject lines, video titles) for each specific context.

ProTip: Use your top questions as subject lines

What’s the most common question people ask you? Or ask your sales team? Or your customer service team? Use that exact question as your next email subject line. Your own audience is the best source of insights.

Your next great subject line is waiting for you in your email inbox, webinar Q&A or chat logs.

7. Use words that indicate visuals

Here’s another way that word choice can increase open rates.

If the email is promoting an article with a chart, diagram, infographic or video, mention it in the subject line. Ours is a small dataset, but we’ve noticed an uptick in open and clickthrough rates when we use an image word in our email subject lines.

Here are examples with those words highlighted:

  • Pictures of their desks: 26 top marketers take us inside
  • This flowchart shows the entire content creation process
  • How much do marketers make? 5 charts that show salary trends
  • 44 marketing diagrams: Swipe files of visuals you can use in your content
  • 7 charts that show how to make better marketing decisions

Compared to other subject lines with other types of words, these have outperformed. And it makes sense. Just like numbers, an image word indicates that the content will be easy to consume.

If you’re using visuals in your content marketing, here are a dozen other ways you can use those visuals to drive ever better results.

8. Write meaningful preheader text

After the sender name and subject line, the preheader text is the next most visible element of your message in the inbox. It is another way to indicate the benefits of reading and increase email open rates.

This is your final chance to get clicked or tapped.

But a lot of digital marketers pay little or no attention to the preheader. They let the email service put a default message at the top of the email, and that first line of text gets used as the preheader.

Each example of preheader text in this screenshot is accidental or lazy. None of them gives the recipient any reason to open. These are all terrible preheaders:

  • “Can’t see this email? View message in a browser”
  • “Follow us on Facebook”
  • “Add us to safe sender list”
  • “Click here to unsubscribe”

The preheader text deserves the same loving care you’d give your email subject line. Just ask Ann.

Ann Handley MarketingProfs

The preheader text is your whispered aside. Everyone strains to hear that whispered aside. Challenge yourself a little with that Preheader! Use it!

  • Put the ACTUAL offer in the preheader (and in the email itself). Use the subject line to test that offer. Baller move.
  • Personalize the preheader — use someone’s name or info in it. Everyone personalizes the subject line — what if you thought differently?

Send a test email message to yourself. Look at it in your inbox. Don’t open the email. Just look at the message and ask yourself: Is the preheader meaningful? Descriptive? Interesting? Is it getting truncated?  Would you click on this?”

Yes, the top line of text in your email messages is actually highly visible in the inbox. If it’s bad, consider a new email template or the first line of the email message body copy.

9. Send every email twice

For the last five years, for most of our newsletters, we send them twice. The first send is to everyone. The second is to those who didn’t engage with the first email. The process is simple:

  1. Send your entire list the email newsletter
  2. Wait five days
  3. Generate a list of the recipients who didn’t open the newsletter.
  4. Send this list a second newsletter with a different subject line

According to our Analytics, the second email increases total open and clickthrough rates by 15% – 30%.

You can clearly see the impact in Analytics. The larger first spike in traffic is the first email, sent on Thursday. The smaller second spike is sent on Tuesday.

Here is the Traffic Acquisition report in GA4:

Does this sound overly aggressive?

It shouldn’t. If you truly believe that the article will help them, you should feel no hesitation in trying twice to reach them. They subscribed because they want to get your content. If they get tired of your emails, they can always unsubscribe.

10. Clean up your email list

Those old, inactive subscribers are dragging down your open rates. Purging them from your email list will immediately improve email open rates.

Sending a lot of low-performance campaigns can also hurt your reputation with the inbox providers, which can hurt the deliverability of your emails for everyone you send to. Jo Wiebe pointed this out. In fact, this was her first tip for better open rates.

Joanna Wiebe Copyhackers

“Clean your list regularly to remove people who don’t open your emails anymore… because low open rates can negatively impact deliverability overall, which further hurts your open rates.”

If you want to give a final push to get these less engaged subscribers a final chance, send a re-engagement campaign, inviting them to interact before you cut them from the list.

11. Use email authentication to improve deliverability (DKIM, DMARC, SPF)

If they don’t get the message, they can’t open it.

It’s rare for us to ever recommend something we haven’t tried and tested ourselves, but this tip has come up twice in two months, from two different contributors. When we’ve reached out to experts for email advice, they’re recommending email authentication.

Joanna Wiebe Copyhackers

“Make sure you’ve got email authentication (DKIM, DMARC, SPF) in place – so your email is “coming from” you instead of from your CRM. After all, your CRM may actually have a low sender reputation – whereas non-spammy you can / should have a great sender rep.”

Here’s the idea: with an extra bit of technical work, the inbox providers can validate that your emails are coming from you, rather than coming from a spammer or a phishing attack. This reputation boost can improve deliverability and keep you out of the spam folder.

There are three methods and standards for authentication: SPF, DKIM and DMARC:

  • SPF (Sender Policy Framework) lets you specify which IP addresses are authorized to send emails on your behalf.
  • DKIM (DomainKeys Identified Mail) is an encrypted signature that verifies you as the email sender, using an email authentication protocol.
  • DMARC (Domain-based Message Authentication, Reporting and Conformance) combines the results from SPF and DKIM to validate the identity of the sender as you.

You can find a detailed post with instructions here on Copyhackers. We’ll be doing this ourselves soon. Then we’ll update this post with the impact on our email deliverability.

12. Send welcome series emails

Some emails have much higher open rates than others. You can increase your overall open rate by sending more high-open rate emails.

The emails with the highest open rates are typically the automatically-sent welcome series emails, that are triggered when you have a new subscriber. They’re set up in your email service provider or marketing automation system on whatever schedule you decide.

Ours is a short, 3-email series.

  • Immediately after the new subscriber signs up, they get a welcome email.
  • One week later, a second email goes out, sharing one of our most practical articles.
  • Two weeks later, they get a third email, with another of our best articles.

Very likely, the open rates for these emails is above your typical campaigns. As you can see from our welcome series emails, open rates are between 30% and 40%.

Why are welcome series email open rates so high?

There are two reasons:

  • Unlike other emails, the timing of these is triggered by the visitor. So they are sent when the subscriber’s interest is high. They’re new to your list.
  • Unlike other emails, you can continue to optimize for better open rates, tuning up the subject lines, using words you know to be effective based on results of past campaigns.

13. Use social media to test email messaging

What was your top performing post on social media? Look at your social media analytics. Whichever post had the best engagement on social will probably work well as an email subject line. You should at least consider using words and phrases from your most-engaging social posts in your email marketing.

Your next great subject line is waiting for you in Facebook Insights or Twitter Analytics.

ProTip: Test subject lines on social media

Write several subject lines and use them as social posts over several days. Use the social post that got the most engagement as your article’s email subject line.

This takes advantage of the differences between promotion channels.

  • Social media is data-rich and low-stakes
    (variety of engagement metrics, you can post the same content many times)
  • Email marketing offers less data and is high-stakes
    (fewer metrics, you can’t keep sending the same email too many times).

Learn things in one channel. Then apply to another channel. Similarly, paid search marketers often use paid social to test phrases and calls to action for Google Ads campaigns.

Email marketing metrics: Beyond email open rates

Now we’ve covered the email marketing best practices that improve open rates. Next, let’s review the email marketing metrics themselves and look closely at how open rates are calculated. As with all reporting in digital marketing, the reports are never 100% accurate.

Open Rates

The tracking of emails is a little bit strange. To track email opens and open rates, email ESPs add a tiny invisible pixel to every email. If this pixel loads, they know the email was opened.

But some subscribers may have images turned off, so some opens are never recorded. Other subscribers may open the email from several locations, so some opens are recorded multiple times.

These are the inherent challenges that come with email marketing. And it’s fine. The goal is not to have perfect data. The goal is useful insights. We only need information accurate enough to guide our next decision. Ongoing improvement is key to every email marketing strategy.

Jessica Best, BetterAve

Open rates aren’t as useful as they used to be. Ever since iOS15 rolled out that little “privacy” feature where they pre-open any email that comes to one of their devices… Which is about 50% of the device world. Most email marketers have seen 50-100% increases in their open rates since September 2021 unless their ESP has mitigated for the change.”

What is a good email open rate?

The average email open rate is 30.4%.

That’s based on analysis of 200M messages from across all industries, as of June 2022. A good open rate is anything in that range.

Clickthrough Rates

This is the percentage of delivered emails that get clicked.

Warning: Any link or button that gets clicked affects your clickthrough rate, even if that link didn’t go to your website. So not all clicks drive traffic. These clicks might support some of your goals (simple awareness of your brand) but not others (traffic and conversions). Be cautious and deliberate when linking to anything but your own site from your own emails.

Any links or buttons that bring people to your website, need to have campaign tracking codes added using a URL builder. This gives you your next level of campaign metrics.

Click To Open Rate (CTOR)

If you want to see how engaged recipients are after they open, this is a useful metric. The Click to Open Rate is the percentage of unique clicks and unique opens for your email campaign.

In other words, of the recipients who opened the email, what percentage clicked? It’s a useful way to look past the factors that affect open rates, so you can focus on the factors that affect clickthrough rates.

It shows the effectiveness of the creative part of the email content separate from the sender name and subject line.

These 5 email aspects…

…mostly affect…

1. Sender name Open rates
2. Subject line Open rates
3. Preheader text Open rates
4. Email body Click through rates
5. Call to action Click through rates

Post Click (Website Engagement) Metrics

Your ESP (email service provider) reports on open and click through rates, which is great. But Google Analytics reports on what the visitor did after they clicked on the email and landed on your website. You’ll need both to get the complete picture.

email engagement website engagement

Without campaign tracking code on every link and button that bring the visitor to your website, you’ll never be able to compare the website engagement metrics (bounce rate, engagement rate, time on page and conversion rate) for visitors from various campaigns.

Other email marketing metrics

Those are the classic metrics. But think about all the other ways in which we interact with email and you’ll soon realize that there are many other ways to measure success.

Let’s put a bow on this post with a few final thoughts from Ann and the value of more qualitative metrics and subscriber feedback:

Ann Handley MarketingProfs

Email is a relationship, not a single acronym. Patterns over time in several metrics are more useful than any single, specific one. That’s especially true now that Open Rates are a hot mess. So maybe…. Roll your own metrics based on your email goals.

Open rates and CTRs are important (the latter especially on direct response emails). But what about longer timelines, when nurturing is the goal and relationships matter most?

Here’s what I track with my own email newsletter:

  • OSR (Open to Save Rate)
    Do your customers Save your emails?
  • OWBR (Open to Write Back Rate)
    What percentage of people open a dialog with you? Especially on that critical Welcome email.
  • RR (Resub Rate)
    When people change jobs, do they resubscribe with their new email?
  • TUPER (Trust U with my Personal Email Rate)
    How many subscribers find you so valuable that they invite you into that protected personal inbox? (We all have one.)

Sure, these metrics are anecdotal. So what? The anecdotal feedback of those metrics is no less useful than hard-math metrics.

The root of the word “anecdote” comes from the Greek “things unpublished” and later interpreted in 17th century France as “secret and private stories.”

You, too, can have your own secret and private stash of email metrics.

They will call you to a higher place.

Gratitude and a recommendation

We are so grateful to our contributors. Ann, Peep and Joanna are not only some of the best writers in marketing, but they are each founders of the companies with the best digital marketing courses on the web.

We recommend you subscribe to each, even if only for a short time, to see what great email looks like:

You will learn so much. I can’t overstate the value of their content or how much I’ve learned from each of them.

There is more where this came from…

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