Email Deliverability and Email Sender Reputation Score: What Marketers Need To Know

If an email is sent and no one receives it, do its contents even matter? Email deliverability remains a mystery to many marketers. Many emails never reach a subscriber’s inbox – but with good planning, you can avoid your message falling through the cracks. 

There are many common misconceptions about email deliverability, and just as many tools to improve it. But first, let’s define deliverability, email deliverability vs. the delivered rate, and the email sender reputation score.

What is email deliverability?

Email deliverability measures where (and if) your emails land in a customer’s inbox (as opposed to, say, a spam folder). If you have poor deliverability, your customers will not receive your email. And if customers do not receive your emails, they’re not going to open and engage.

How email deliverability is different than email delivered rate

Email deliverability is different from an email’s delivered rate. If email deliverability measures where and if an email lands in a prospect’s inbox, the delivered rate measures the number and percentage of emails that don’t hard bounce or soft bounce.

• A hard bounce is an undelivered message such as one sent to an invalid address. 
• A soft bounce is a message undelivered despite the email address being valid. Usually these messages end up in spam folders or a promotions inbox. Your subscriber receives it, but does not see it. 

A campaign can have a high delivered rate and still have low deliverability. Confusing? You bet! 

Here’s what you need to know: The email delivered rate does not take into account where the message lands in the recipient’s inbox. The email deliverability rate does.

Email deliverability is a crucial metric in an email marketing strategy. Even if you design beautiful, personalized campaigns every week, your sender reputation score determines whether or not your subscriber will receive your message.

What is an email sender reputation score?

Internet service providers (ISPs) such as Comcast or AT&T look at a myriad of data points and factors to determine whether they’re going to accept or reject an email message. These data points also govern where the message is delivered – the prized inbox or the lowly spam folder. 

Think of a sender’s reputation scoring like a credit score. In finance, past spending and payment history is rolled into an equation that determines whether a lender will trust you with a new loan or credit card. Like credit bureaus, ISPs use scoring algorithms to determine the validity and usefulness of your email. Each assessment is proprietary, so it’s possible to have a good reputation with one ISP but not another. 

How to determine your email sender reputation score

The higher your organization’s email sender reputation score, the more likely it will be for your communications to land in the right place for your customers and prospects to engage. Take a hard look at these metrics from your email subscriber list to get an idea of how much clout your communications have with ISPs:

• Bounce rate: In web traffic, this is the percentage of website visitors who navigate away from the site after viewing only one page. In email campaigns, this is the number of recipients who open, click, reply to, forward, and delete before opening an organization’s messages. Email senders with lower bounce rates are more likely to land in an inbox.
• Unsubscribe rate: This is the percentage of recipients that unsubscribe after receiving an email message. It’s expected for some number of recipients to unsubscribe after every send. But an excessively high percentage of unsubscribing recipients is often an indicator that your email is unwanted.
• Number of spam trap email address recipients. A spam trap is an email address that does not belong to a real person, and they often identify organizations with irresponsible list building techniques (such as buying email lists). ISPs, spam/security appliance vendors, and blacklists all maintain lists of spam trap addresses. If you send email to spam traps, it’s an indication that you’re not keeping your email list clean. The value and validity of your message will take a hit as a result.

How to protect your email sender reputation score

• Use double-opt-in and reactivation campaigns. With more security and signals of human interest in receiving your emails, you can make sure that an email address belongs to a real person and avoid spam traps.
• Keep your email list clean. Purge your subscriber list regularly and remove bouncing, invalid email addresses and non-responders.  
• Implement an IP warm-up plan. Target a first round of subscribers that are most likely to engage, including those who’ve opted-in most recently, and those with a good track record of engagement. Slowly inIncrease the campaign’s volume of recipients week over week. This methodology builds up your trust with ISPs.
• Make your emails actionable. The more your customers click and interact with your email content, the higher your email sender reputation score. This signals that your emails are valuable to the recipient (and a strong CTA is probably better for your business, too).