How important is a reputation? At work, within your community, within your family…a reputation means a lot. And it has to be protected. As Benjamin Franklin is famously quoted as saying, “It takes many good deeds to build a good reputation, and only one bad one to lose it.” 

This need to build and protect a reputation exists in the email marketing world too. Your email marketing can’t exist unless your emails are being delivered to the people on your subscription list. But you’re only allowed to send those emails to those people if you have a good reputation in the eyes of the Internet Service Providers (ISPs) who can either let those email through or not. Just like you wouldn’t want one of your kids hanging out with someone with a bad reputation, the ISPs don’t want to let any email marketers with bad reputations into the same inboxes as those with good reputations.

Why This Emphasis on Email Reputation?

ISPs look at your email reputation—also known as your sender reputation—as indicative of how trustworthy you are. When spam makes up almost half the email sent daily, ISPs want to do what they can to keep that spam out of their customers’ inboxes. If you’re not trustworthy, you might be a spammer, and hence, the importance of your email sender reputation. 

This matters to your ROI because decreased deliverability is the downside of a poor email reputation. If you have a list of 100,000 names on your list, but you have a poor reputation and major ISPs like Gmail and Yahoo are blocking your emails from getting through as a result, you might only get into half of those inboxes—or less. On the other hand, a good reputation can help to increase your deliverability which in turn can improve it even more:

The more inboxes you get into, the more opportunity you have for recipients to interact with your emails. And when people are opening your emails, they are silently telling the ISPs that you’re a legitimate sender, thereby improving your reputation even more. 

When even a small bump up or down can have an effect on deliverability and therefore ROI, your reputation should be a big deal. So while ISPs are keeping a close eye on your email reputation, you should be as well. 

Your Email Sender Score and the Effect on Deliverability

A quick stop at is the easiest way to discover your current email reputation. The Return Path Sender Score will give you a detailed email reputation check, with the information you can act on. You can get the apartial report in seconds, or you can register for a full report. Either way, the service is free but at the same time invaluable.

6 Factors that Affect Your Email Sender Score

In order to understand your sender score, it’s important to understand the factors considered by the ISPs when they try to determine your trustworthiness. Below are six of the factors considered and how you can do a better job at each as an email marketer.

1. Longevity: The longer you’ve been sending emails, the better, because spammers tend to be hit-and-run type senders, quickly switching IP addresses as they get shut down, then moving on to another. You can’t alter time, so if you’re a new email marketer, you’ll have to be patient as you wait to build a reputation. As you’re waiting, make sure to adhere to every deliverability best practice! That will help. 

2. Send volume: Spammers tend to send a lot of emails all at once because that increases their chances of actually tricking someone. For you, a huge volume will make you suspicious in the eyes of the ISPs, especially if you’re all of a sudden sending significantly more email. If you’ve just switched email service provider (ESPs), follow their advice to ramp up your new IP address slowly, sending low volumes of email as the ISPs get to know the new you. If you’re already an established emailer, avoid suddenly or sporadically sending huge volumes. If you look at your sending through the filter of the ISPs and the attitude of “if it looks like spam…”, it will help you to check your own sending behavior when necessary. 

3. Spam traps: Speaking of spammers, they typically have spam traps on their lists. A spam trap looks like a valid email address but is quite literally a trap used by ISPs to spot spammers. If you’ve been sloppy when building your email list, you could very well have spam traps on your list. And if you send to those spam traps, guess what the ISPs will think? Yep: spammer. There are two ways to avoid spam traps: Build a list based on quality, not quantity, and practice regular list hygiene to keep your list clean.

4. Spam complaint rates: How else do ISPs spot spammers? Consumers. The people getting your emails can easily report your emails as spam with the click of a button. And lest you protest by saying you only send to people who subscribed, note that people will report an email as spam rather than unsubscribe just because they don’t want to get it anymore. To avoid being reported as spam, use best practices, make unsubscribing incredibly easy by putting the link at the top of your template, and pay attention to inactive subscribers so you can take them off the list and message them separately. 

5. Bounce rates: Emails will bounce. There isn’t anything you can do about that. But you need to pay attention to bounces. Remove hard bounces a.s.a.p. and monitor soft bounces to see if those names also need to be removed from your list. 

6. Blacklists: Yes, even good emailers get blacklisted, so don’t assume it can’t happen. Make sure you’re not blacklisted by using the checker at Should you discover that your domain is in fact on the list, do everything you can to clean up your act and adhere to best practices, reaching out to the major ISPs if you need to plead your case. 

How to Maintain a Good Email Reputation

If you’ve checked out at, and you understand how to behave well according to the six criteria above, maintenance is your next step in protecting your email reputation. Make sure to practice good list building and list hygiene. Monitor your sender score and deliverability on a regular basis, so you can take action if you see a blip. Test to determine what kind of frequency and content work best with your audience. Segment as much as you can so you’re sending more targeted messages to smaller numbers of people. And monitor, monitor, monitor that reputation.

Increasing your email marketing knowledge will help too, as email is a field of constant change and you need to keep up to stay effective. Simplilearn’s Advanced Email Marketing Certification Training can help ensure you are adhering to the latest best practices and keeping your email sender reputation intact. 

Repairing a damaged email reputation is not an overnight fix, even if you didn’t technically do anything wrong, and you can’t start sending emails as if everything were back to normal because you have to rebuild that reputation. It can be a long, expensive road back to a good reputation. So protect it from day one. 

Our Digital Marketing Courses Duration And Fees

Digital Marketing Courses typically range from a few weeks to several months, with fees varying based on program and institution.

Program NameDurationFees
Post Graduate Program in Digital Marketing

Cohort Starts: 29 Aug, 2024

8 Months$ 3,000
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Cohort Starts: 5 Jun, 2024

8 Months$ 1,649