You can design the most visually spectacular mass mail packed with eye-catching imagery and engaging copy, but none of that really matters if you can’t get the subscriber to open it in the first place.
After deliverability, email open rates are the next most important thing in any email campaign. Remember – the clickthrough and conversion rate of unopened emails is 0%. There’s no getting around that simple fact.
The question, then, is how do you make sure those emails are getting opened in the first place? What tips and tricks go into successfully increasing email open rates? And even if you’re happy with your currency open rate, there’s always room for improvement. What can you do to ensure email open rate optimization?
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What is the Average Email Open Rate?
Open rates tend to vary across industries, with some as low as 15% and others getting up to close to 25%. That said, the average open rate across all industries (according to MailChimp) is 21.33%. This is the absolute bare minimum, then, that you and your company should be aiming for.
8 Proven Tips and Tricks for Increasing Email Open Rates
With that in mind, let’s take a look at 8 proven tips and tricks for increasing your email open rates.

Prune Your List Regularly
Unfortunately, it’s often the case that people who subscribed to your mailing list quite simply aren’t interested anymore. It’s also not uncommon that subscribers have switched email addresses and your emails are simply filling up a bloated inbox that nobody’s checking.
In either case, there’s no point in having unengaged subscribers on your mailing list. Such subscribers adversely affect the health of your list, including dragging down your open rate. It’s therefore important to stay on top of your mailing list and ensure that you get rid of any unengaged subscribers who – for one reason or another – aren’t opening your emails.
By doing this regularly, you’re ensuring that your mailing list is filled with engaged, high-value subscribers that are likely to open your emails, and thus click through and convert. All of this results in higher email open rates overall.
Make Sure Your Emails are Relevant
How many emails do you gloss over daily in your inbox because you’re simply not interested? Many of these emails will have been sent without thought or regard for whether or not they’re engaging to subscribers, simply because if you send enough emails to enough subscribers, some of them will get opened.
This is a wrongheaded way of looking at email marketing, and should be avoided by anyone looking to increase their email open rates. To return to our example of your inbox – what emails did you open today? Was it for a new item that had just come into stock that you’d been waiting for? A newsletter from one of your favorite brands? An invitation to enter a particularly compelling competition?
We open emails that are interesting and relevant to us. This means that your email campaigns should be interesting and relevant to your subscribers. Of course, it’s difficult to craft a single email that will appeal to every single person on your mailing list, and that’s where automated segmentation comes in. People who haven’t engaged in a while should receive very different emails from highly loyal customers who make frequent high-value purchases, for instance.
Provide Valuable Content
If the content of your emails is weak and unengaging, you can expect your subscribers to quickly become turned off and uninterested in your emails. Even if they don’t unsubscribe, they may simply stop opening your emails – which is actually worse, as it will affect the health of your mailing list.
How can you avoid such a fate? As we touched upon in the previous entry: by providing quality content. And that means content that doesn’t come across simply as “please buy our stuff.”
Content marketing is increasingly popular precisely because it works. By leading with interesting content first and foremost, you’re likely to see much higher open rates. If you’re a company offering organic produce, send your subscribers a collection of delicious recipes that make use of your produce. If you sell running shoes, compile a list of beautiful scenic jogging routes nearby individual subscribers.
The more subscribers get quality content from you, the more they will anticipate future emails from you – and your open rate will almost take care of itself.
Segment your List
We mentioned list segmentation earlier, but it’s worth reiterating because of just how important it is.
Segmentation isn’t just important to email open rate optimization – it’s important for every aspect of email marketing. It’s invaluable not only in sending subscribers the type of content they want to see, but also when it comes to sending out emails relevant to purchase history, recent activity, and even subscriber engagement levels (e.g. sending out a ‘we haven’t heard from you lately…’ email).
Research has shown that segmented email campaigns experience open rates 46% higher, on average, than those of traditional email campaigns. When you consider that the average open rate is around 21%, that’s huge.
The best part is that segmentation is generally done automatically if you make use of an automated email marketing platform like Hubspot. That means that not only do you get much better open rates, but you don’t have to lift a finger to get there.
Use Effective Subject Lines
Your subject line is perhaps the most important aspect of ensuring that your emails get opened. It’s the first thing subscribers see, followed by your preview text, and so making an impression with it is crucial.
Writing a good subject line is an art in of itself. Let’s take a look at some of the most important aspects when it comes to nailing that subject line.
Don’t Use Cheap Gimmicks or Tricks
Promising a reward or discount in your subject line to entice subscribers to open might work, but if you’re not actually offering that reward, all you’ve done is mislead your subscriber, undermined the reputation and trustworthiness of your brand, and likely won yourself an unsubscribe.
That’s why it’s important never to lie or mislead in your subject line. It needs to be honest and straightforward – that way, your subscribers know that you can be trusted to do as you say.
Use A/B Testing
When coming up with ideas for killer subject lines, you may find that you end up with two really solid options that you simply cannot decide between. Fortunately, that’s where A/B testing comes in.
A/B testing allows you to send two variations of the same email out simultaneously to a small portion of your mailing list. You can then analyze the data generated by that (open rates, CTR, conversion rate etc.) and make a decision on which one you’d rather send to the rest of your mailing list.
With some automated email marketing platforms, in fact, you don’t even need to analyze the data and make that call yourself. The data can be automatically analyzed by the platform and the more effective of the two emails sent out without any further input on your part. It couldn’t be easier.
Keep It Fresh
If there’s one thing that gets stale very quickly, it’s repetition. Avoid using samey language or repeating the same phrases or words in the subject lines of your various emails, or your subscribers will quickly get bored and soon stop opening them.
Avoid Spam-Like Words or Language
The past 25 years or so of popular email use have primed us all to be on the lookout for spam, to the point where we can immediately recognize anything that sounds even vaguely ‘spammy’. Even if such emails make it past the increasingly sophisticated spam filters of most major email providers, chances are that subscribers will immediately archive them without so much as a second look.
Avoid using anything, then, that will make your emails sound like spam. Excessive use of exclamation marks, writing the whole subject line entirely in capital letters, colored fonts, overly urgent calls to action, and much more can lead subscribers to immediately peg your email as spam, and thus disregard it.
A more comprehensive list of words and phrases that seem like spam can be found here.
Should You Use Emojis?
Something that is still very divisive in the email marketing community is whether or not emojis should be used in subject lines.
The conservative answer would be ‘no’. Conventional wisdom holds that you should appear as professional and accurate as possible, and that emojis are the opposite of both of those – they are both overly familiar and, by their very nature, overly ‘slangy’ and improper.
The flip side of that coin is that emojis make for subject lines that are more intimate and personal than conventionally accepted subject lines. We’d send emojis to our friends, after all, so why not use them in emails to our subscribers?
At present, the data collected on emoji use in subject lines suggests that, after an initial burst of enthusiasm for them, the numbers have actually dropped off. As of 2022, emoji-laden subject lines have a lower open and clickthrough rate than those without – their open rate is about 20.45%, compared with 21.94% for non-emoji subject lines.
Why the sudden change? Much like official Twitter accounts that used jokes and sass to give off the impression of being hip and ‘down with the kids’, consumers quickly cottoned to the act and stopped buying into it.
With that in mind, it seems that subject lines with emojis have already had their time in the sun, and it’s likely best to steer clear.
Keep it Short – but not too Short
How long should your subject line be? The temptation, of course, is to keep it short and sweet. People generally have short attention spans, and so it seems to make sense to try to hook people as quickly as possible.
Traditional email marketing wisdom holds that you should keep the length of your email subject lines to about 50 characters – and this is, indeed, the length that most email marketers swear by, with about 50% of all mass mails sent clocking in at between 30-50 characters.
However, the biggest open rate – about 32% — was for emails with subject lines of a whopping 220-230 characters. Open rates for emails that fell into this category were around 32% — 10% or so higher than the average open rate across all industries.
Should you crank up the length of your subject line, then? Not necessarily. The shorter your subject line, the more control you have over how it’s displayed to your subscribers. You also need to be aware of the fact that many subscribers will be viewing your email on their mobile devices, and an overly long subject line may end up getting truncated. You’d ideally like to avoid this, so don’t go too long.
Grab the Subscriber’s Attention
What kind of emails get opened the most? Those that immediately pique the interest of the subscriber. Subject lines that are capable of doing that include:
Contrasting Ideas
“Apple pie and Rocket Raccoon” makes absolutely no sense. It also immediately stokes the interest of the subscriber, and leads them to open your email to see what, exactly, you’re talking about.
This gimmick can be overused (and thus lead to a long-term drop in open rates) but, when used sparingly, it can be extremely effective.
Urgency
“Offer ends at midnight!” or “only 3 left in stock!” both create an immediate sense of urgency and can induce FOMO (fear of missing out) in the subscriber.
As with contrasting ideas, though, this should be used sparingly; if overused, it can rapidly lose effectiveness. It’s also not a million miles away from spam tactics, which you don’t want to be associated with.
Casual Language
Using friendly and informal language makes your business seem less like a business, and more like an organization comprised of normal people just like you and me. Using slang and less formal language is, therefore, generally quite effective. Just don’t overdo it (by using emojis, for instance).
Use Preheader Text Effectively
After your subject line, the preheader text is the next thing that your subscribers are going to see. It’s important in creating a good impression and therefore drives email open rates. That’s why it’s a terrible idea to simply leave it on the default setting of displaying the first line or two of your email – this will often lead to dull preheader text like “having trouble seeing this email?”
Just having preheader text can increase open rates by around 8% — so it’s well worth taking the time to write one. Good preheader/preview text will:
- Summarize the contents of your email;
- Detail a discount or promotion in brief;
- Pique the subscriber’s interest and lure them in.
Spending a little time on making sure your preview text entices your subscribers, then, is very much worth it, and can go together with your subject line like cookies and cream. In order to make the most of your preheader, bear the following in mind:
- Don’t go above 100 characters. Any more, and it’ll be too long to display on mobile devices.
- Use compelling language that rouses the subscriber to act, e.g. “act now to get 15% off!”
- Don’t use ellipses (‘…’), as it suggests that the preheader text has been cut off.
- Use A/B testing to see which preheader text is more effective.
- Make sure your preheader text is optimized for assistive technology, such as screen readers, so that subscribers with disabilities are able to hear it.
- When appropriate, make the preheader text mysterious and intriguing, to pull the subscriber in and compel them to open the email itself.
Customize the Sender Name
We’ve talked a lot about the effectiveness of being more intimate and personal with the subscriber in order to induce them to open your emails. A surefire way of failing to do this is to email them from a bland, impersonal business email address. If you get an email from “sales@emailmarketing.com”, there’s a good chance you’re going to leave that email unopened. It’s clearly a mass mail that’s not been sent with you in mind, so why bother?
Instead, emails should be sent from addresses that use actual names. The above email is much more likely to be opened if it’s from Sara@emailmarketing.com, because it creates the impression that there’s a real person at the other end of the email, rather than some automated email marketing platform unthinkingly sending out thousands of emails at a time.
Conclusion
Improving your email open rates is a fine art, in many respects, and there are a lot of moving parts to keep track of in order to nail your email open rate optimization. However, if you bear in mind the holy trinity of open rates – subject line, preheader text, sender name – then you can’t go too far wrong.
Don’t forget, either, that automated marketing platforms can be a massive help when it comes to further optimization (like segmentation and personalization). If you want the best possible open rates but don’t want to spend too much time figuring out how to achieve that, tools like those offered by the likes of Hubspot and Mailerlite can be invaluable.