When it comes to email marketing, nothing is as important as getting your message across. This means you need to make sure that your email lands in the right place – your recipient’s inbox. And if you’ve ever tried sending an email marketing campaign, you’ll know that it’s easier said than done. There are a lot of obstacles placed by Internet Service Providers (ISPs) in order to protect their users’ inboxes from spammers and harmful content. And depending on your sender reputation, you may be considered one of them. So, how do you find out your sender’s reputation & your sender score?

what is a sender score EmailOversight

What is a Sender Score? 

Your mailbox provider is responsible for two things – making sure that you get the messages you want to receive and blocking any unwanted messages (i.e. spam) as well as harmful content. In order to accomplish this, a mailbox provider will check the reputation of the sender.

Sender reputation is like your credit score. Your credit score determines whether or not you are trustworthy, especially when it comes to handling money. In a similar way, your sender reputation lets mailbox providers know whether you are legitimate and to be trusted which can affect your email deliverability. And just like your credit score, your sender reputation is measured using various metrics which will differ depending on the ISP (Internet Service Provider).

So, what is the sender score? Well, there are several organizations that measure sender reputation, which is a range of points from 0 to 100 which shows the health of your email program. To determine the Sender Score, data is compiled from millions of inboxes from different ISPs and records activities such as spam complaints, the number of spam traps triggered, the number of invalid users on an email list, and the number of people unsubscribing certain email senders. Based on the data gathered, Sender Score is assigned to you, which is a rolling 30-day average of your email sending habits and the response of your recipients.

Take note that not all ISPs will use your Sender Score in order to determine whether to deliver your email or not. But the metrics used by the most mailbox providers determine sender reputation. In short, it can help you stay aware of your sender reputation and enable you to fix any deliverability problems as soon as possible.

What is a Good Sender Score? 

Obviously, the higher your Sender Score is, the healthier your sender reputation is. But what is a good Sender Score? If you have a Sender Score higher than 80, then you have a great sender reputation. Just keep what you’re doing and follow the best practices in order to protect your sender reputation. If your sender score is between 70 to 80, then you’re doing something right but your email program still needs optimization. It’s not a good score but it’s not a bad score either. To improve your score, make sure that you’re following all industry best practices. Check which aspects of your email program is lacking and requires improvement.

What is a Bad Sender Score? 

Any Sender Score below 70 means that you have a poor sender reputation and it needs to be repaired. There’s something wrong with your email program that’s affecting your deliverability. If you score lower than 50, you may be considered a spammer – someone with a poor reputation and questionable sending practices.

email sender score and email deliverability Emailoversight

Sender score and email deliverability: 

As we’ve already mentioned, your sender reputation has a high impact on your email deliverability. Since your sender score is an evaluation of the health of your email program, it is a good indication of your sender reputation as well as a good prediction of what your email deliverability is like. The average delivery rate of senders with a sender score above 90 was 92%. This means that on average 92% of the email they send gets delivered to the recipient. Those with 80 or below may get more than half of their emails rejected by the gateway filter.

How do companies benefit from a high sender score? 

Reputation is important for any company. And we’re not just talking about brand reputation. In the world of email marketing, your sender reputation can make or break your campaign. If you have a high sender score, your email has a greater chance of landing in a person’s inbox on a consistent basis. 92% of your emails will get delivered to the inbox if your sender score is 91 or higher. Because your messages reach the inbox, you get more opportunities to engage with current and potential customers. An effective email campaign can earn you $38 for every $1. In short, a high sender score increases your email deliverability which increases your ROI and your revenue.

What influences email deliverability? 

As we’ve already stated, there are several metrics used by ISPs to determine sender reputation and, as a result, email deliverability. These metrics do differ between the various providers. The good news is that your sender score is a good proxy for all the different measurements used by these mailbox providers. This is why we’re going to take a look at the three key metrics used to calculate your Sender Score. Take note that there are other factors used such as volume, acceptance rate, and external reputation but the main three are the most important.


This is the measurement of complaints made against your IP address in comparison to others. A complaint is made when a recipient marks your email as junk or spam. A high complaint rate signals to the ISP that your content is unwanted and should be sent directly to spam. To calculate the complaint score, the number of complaints is divided by the number of accepted emails and then ranked.

Unknown Users:

Email addresses that have never existed, been abandoned by the user, or terminated by the mailbox provider are considered unknown users. If you send an email to an unknown user, the ISP will return a hard bounce code (5xx) which means that the email was sent to an invalid email address. The unknown user rate is a measurement of how many times you attempt to send an email to a non-existent email address. If your unknown user rate is high, it indicates that you don’t practice good email marketing list management. You either acquire your list underhandedly (scraping, buying) or you don’t clean your list regularly (poor list hygiene practices), both of which negatively impact your sender reputation.

Spam traps:

Spam traps are email addresses that are valid but don’t belong to active users. Instead, mailbox providers use them to catch spammers and senders who practice poor list hygiene. There are two kinds of spam traps that senders should be aware of – pristine and recycled. Pristine spam traps are email addresses that have never been owned by a real person. Therefore, there is no reason for this email address to be on any marketer’s list. Recycled spam traps, on the other hand, are abandoned email addresses (previously belonged to actual users) that were converted into spam traps.

How to protect your Sender Score: 

Your Sender Score is a rolling 30-day average of your sender reputation. As you continue to send emails, your score will be recalculated which means that your score is not static. It will change over time. If you want to consistently run effective email marketing campaigns, you’ll need to make sure that your score remains the same. That means making sure you follow industry best practices such as regularly cleaning your lists, creating interesting content, and being consistent with your volume of email sends.


How to improve your sender score EmailOversight

How to improve your sender score:

The first step of how to improve your email sender score is checking which metrics are affecting your Sender Score. Is it the volume of emails you are sending? Is your accepted rate low? What about your complaint rate and unknown user rate?

If you’re still not sure, here are some tips on how to improve sender score:

  • Warm-up your IP Address: if you’re new to email marketing, don’t start sending a large number of emails as it can hurt your sender reputation. Instead, start slow and send email only to a small group of people, those whom you are sure won’t be hitting the spam or unsubscribe button. Slowly increase the number of emails you send to warm up your IP address and improve your sender reputation.
  • Get off blacklists: if you have a bad sender score, you may be on an email blacklist which is a database of IP addresses and domains that are considered spammers. There are several tools you can choose to check if you are. Contacting the sites that have blacklisted you can help you figure out what to do to get off the list.
  • Clean your list regularly: it’s important that you monitor your hard bounces and remove these email addresses from your active list as soon as possible. You should also use an email validation service to clear out any spam traps that may be included in your list.
  • Be consistent: this means that the amount of email you send and the frequency with which you send them remain the same. If you send 500 emails today, 50 emails the next day, then 1000 the week after, your Sender Score will get dinged. Make sure you create a schedule for your email marketing campaign and that you stick with it.
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