What’s the best time to send? What is the ideal length of a subject line? What magic words will get recipients to open? Email senders have obsessed over these questions for years. 

You can lose hours second-guessing every aspect of your message and format in an attempt to optimize it. You can get into battles over where the link is placed in the email, who the message should come from, or what color the button should be. But even after resolving these debates, you might end up with results that are more or less the same as what you usually see.  

So which of these factors really matters? What do recipients actually care about?

We wanted to find out, so when we conducted the research for our 2019 Email Benchmark and Engagement Study, we asked people on the receiving end of emails to rank factors that influence their decision to open a message or ignore it. The results may not be what you expect.  

Factors that do (or don’t) influence opens

The sender? Strongest influence on opens.

The sender is the most important factor that influences opens. According to our research, 53% of respondents said it has a strong impact on their decision to open an email. 

If your recipients like hearing from you, they will open your emails.

However, if they don’t like getting your emails or they don’t know how they got on your email list, they’re much less likely to engage.

It appears to be that simple. The leading factor that’s affecting your open rate is your recipient’s familiarity with your brand.

You will probably see strong open rates if you have a good relationship with your audience. How do you earn this? 

  • Send email content they want to receive. 
  • Opt them in with clear consent. 
  • Deliver the types of messages you promised. 
  • Don’t bombard them with emails. 

The content? Strong influence on opens.

Content is the next factor that has the greatest potential to impact your open rates. That’s not surprising. This is the heart and soul of your emails. 

However, when it comes to email content, short and sweet is best. 

Don’t get caught in the trap of believing that because content is so important, you should include a lot of it. In fact, it’s the opposite. For 55% of recipients, a few lines is all they want to get from senders. 

They want to be able to open and quickly consume the content. It’s understandable that they don’t want to have to sift through a long message to pick out the information that’s valuable to them, so resist the urge to include more content than you absolutely need. 

The subject line? Some influence on opens. 

The subject line is important, but it’s not necessarily the trojan horse you might think it is. 

In our study, 37% of people said the subject line would have a strong influence on their decision to open while 17% said they don’t know if it would even have an impact. Another 10% either said it wouldn’t really influence their decision or it wouldn’t have an impact at all. 

This is surprising because subject lines usually take center stage in the conversation about how to optimize email results. They are the focus of A/B tests and heated conversations about which words to use (or not use) to influence opens. 

In reality, you may not be able to solve low open rates start with subject line tweaks.

If you create a clever subject line—great. But even if you strike subject line gold, you can’t always expect it to make up for poor email practices elsewhere (e.g. poor content, an unknown sender name, sending too frequently).

Offers and promotions? Some influence on opens.

It’s easy to assume that an offer or promotion would be a fantastic incentive for recipients to open an email. Who doesn’t love a discount or coupon code after all?

But only 35% of recipients said an offer or promotion had a strong influence on their decision to open an email. Another 36% said it might influence their decision, but a full 13% said it wouldn’t influence their decision much or at all. 

The exception here is that offers and promotions are highly effective with certain audiences. They are the strongest influence for Millennials, and also a strong factor for Gen Z and Gen X as well. If you are sending to contacts who fall into this category, this could be an effective strategy to use to drive clicks. 

Just don’t send offers so often that your recipients become numb to them.

And when you do, make an offer that’s undeniably worth checking out. Because, it turns out that promotions may actually make your emails more memorable.

A full 42% of recipients said offers and promotions are a strong influence that can make an email memorable. It was ranked as having a more powerful influence than fun and catchy content, images/videos, branding, or personalization.

Time of day? Minimal influence on opens. 

A real surprise here is that time of day isn’t that strong of a factor in a recipient’s decision to open an email. 

There have been so many reports aimed at finding the silver bullet of email timing and giving us an answer to the elusive question: What is the best time to send emails to get more opens? (We’ve done our own research and produced sound recommendations into the matter.) 

It appears that it doesn’t matter as much to recipients what time you send. They aren’t necessarily more likely to open an email on their commute or when they’re browsing the net in the evening. If the message is from a brand they don’t like or about a product they’re not interested in, they won’t open. 

Likewise, we found that sending an email at one time or another won’t necessarily deter recipients from opening if the content is something they’re already interested in.

While the results showed us that you shouldn’t sweat the timing too much, there are still many use cases where it’s important to have a specific time to send. The Hustle, for example, regularly sends their email newsletter early in the morning. For people who frequently read The Hustle and expect it to be there when they open their inbox, it would be odd to change the timing of the newsletter to the afternoon.

So set up your emails to send when it makes sense for your company and your customers. 

Factors that do (or don’t) influence conversions

Opens are great, but clicks are where the real magic happens.

Clicks are often the closest you can get to a conversion for an email. 

Whether they’re related to viewing products, resetting a password, or verifying a new account, clicks are generally the holy grail for email marketing campaigns.

Even if you have a high open rate, your email might not be considered a success if you don’t have a correspondingly high click rate. 

But what’s behind those clicks and how can you get more of them?

👎 Brand of sender

Your brand name and reputation can get your email opened, but won’t have as strong of an influence on clicks. 

Recipients across the board said this “somewhat influenced their decision to click,” which means you have to do more than have a trusted brand to drive conversions. 

👎 Link optimizations

Link placement, link color, and link copy play some role in a recipient’s decision to click a link in an email, but they’re not necessarily factors that can be manipulated to drastically improve your email performance.

Recipients said link placement would somewhat impact their decision to click, but most report that they don’t know if the link color or copy influenced their decision at all. 

If you’re spending a lot of time changing the link copy or trying to test into the ideal color, you might not be seeing a ton of pay off. What you should do instead is make sure the links in your emails are clear, visible, and that they point to products or information your readers want.

👍 Offers and promotions

On the flip side, including an offer or discount in your email is the best way to get recipients to click, especially if you’re targeting Millennials. Nearly half said an offer or discount has a strong influence on their likelihood of clicking a link in an email. 

An offer or promotion is a great incentive for new users to get them to make an initial purchase or get existing customers to make a return purchase. 

Just don’t overdo it. The majority of participants prefer to receive emails on products that interest them once a week or less often.

Also, make sure the offer is worthwhile. Recipients won’t necessarily be moved to convert if your offer isn’t compelling and it could have the unfortunate side effect of making them numb to future promotions.

👍 Email content

We also confirmed the widely accepted belief that the content of an email has a strong influence on recipients’ inclination to click. 

It makes perfect sense. Without the content there to provide context, why would a recipient click a link or button? 

The images and the words are what convince readers to take the action you want. Whether you’re sending a confirmation email or a promotional message, you need content to explain why an action is necessary and verify that the message did indeed come from a trusted brand. 

It’s an added bonus if you make your email content fun, interesting, or interactive. Catchy or fun content—along with images or videos—are among the top factors that make emails more memorable than the rest. 

👍 Critical information 

Critical information was key for 36% of recipients. They said emails containing password resets, purchase receipts, shipping notifications, etc. have a strong influence on their clicks.

It’s easy to see why recipients respond so readily to information like this. If a message has details they want or need, they will be looking forward to receiving and engaging with that content. 

For email senders, it underscores the importance of transactional messages. Because these emails are a driving force of your engagement program, they should be on-brand and receive just as much design and content consideration as your promotional messages and nurture streams.

Even more importantly, you need to make sure your transactional messages have strong delivery rates to ensure they reach the recipients who have been waiting for them.

👍 Relevant products

There’s nothing better than getting an email that feels like it was made just for you

A message featuring products based on interests, past purchases, or items you’ve recently interacted with stands an immensely better chance of getting your attention than the alternative—a generic email with things that might not appeal to you at all.

Seeing relevant products in an email has a strong impact on clicks for 32% of recipients and somewhat of an influence for another 41%. 

If you’re interested in a 1-to-1 marketing approach that can increase your email clicks, we’ve got a resource that can help—with 6 tips and examples to provide inspiration. 

The takeaway: send emails your recipients will love

Recipients are smart. They’ve learned how to spot an email that’s useful and they’re quick to unsubscribe from senders who don’t respect their inboxes.

Ultimately, the best thing you can do for your email program is to get the basics right. 

  • Send emails with information that’s relevant. 
  • Get to the point with your content. 
  • Don’t treat your contact list like a captive audience. 
  • Send sparingly so you don’t overdo it with volume. 

You can test your knowledge to see how much you know about how recipients interact with email by taking this quiz. Or, you can download our full report to get even more data about what recipients want and how to create a winning email program.



Lauren Kaye
Lauren is a Website Writer at Twilio SendGrid where she writes and edits content for SendGrid.com. After working as a Marketing Editor for an agency on the East Coast, a Sr. Copywriter for a travel brand, and an English teacher in Spain, she loves the challenge of writing about Twilio SendGrid’s innovative communications platform.