What is Sender Reputation?

Online security is a huge deal nowadays. Everyone wants to be safe online, from protecting our personal information from getting stolen to safeguarding our websites from cyber attacks. Did you know that Email Service Providers take security very seriously, too? Yes, the last thing a reputable email provider wants is for its users to be getting all sorts of malicious and dangerous emails. So, they take extreme care to optimize their filters and only allow "good" emails to pass through. There are many things that factor in determining which email is "good" or not. One of the most prevalent factors is sender reputation; we are here to tell you all about it.

This post includes:

• What is Sender Reputation?
• Factors and Metrics that Affect Sender Reputation
• Other Ways to Improve Reputation

What is Sender Reputation?

As the name suggests, sender reputation is a score determining if an email makes it to the recipient's inbox or spam folder or is turned away entirely. Naturally, the higher this score is, the more Email Service Providers will trust your emails, and you will have fewer issues with deliverability. But what exactly is this nebulous "reputation"?

The score needed for a good sender reputation is determined by each mail provider individually. However, they are usually pretty similar, so you would not have to do something super specific, just so your emails are allowed through that one provider's filters. The score itself is determined by two things: IP and domain reputation.

Your IP reputation relates to the IP you use to send your emails. It can be the IP of your domain's hosting server or an entirely separate one if you are using a different service for your outbound mail. For example, we provide a complimentary email service with all our hosting plans, but our Shared Hosting servers benefit immensely from SpamExperts. It allows our users to send their emails from SpamExperts' IPs instead of those of our hosting servers. SpamExperts' IPs are immaculate regarding their reputation because the whole point of their service is to not let any malicious emails or spam be sent. Each IP online has its own reputation, which tells mail providers how trustworthy the emails coming from it are.

On the other hand, you have your domain reputation. It is similar to the IP reputation but regarding your domain. Likewise, each domain has its own reputation, which tells Email Service Providers how trustworthy the emails it sends are. 

A combination of IP and domain reputation determines sender reputation. Mail providers do not want their customers to get spam or dangerous emails, so they filter out any messages from IPs or domains with poor reputations. Read on, and we will explain the factors that determine this reputation.

Factors and Metrics that Affect Sender Reputation

To determine the reputation of an IP or a domain and, therefore, of a sender, there are several factors and metrics that must be taken into account. Below, you will find a list with in-depth explanations.

• Bounce Rate - Bounce rate measures how often your emails fail to be delivered, regardless of the reason. A high bounce rate will tell the mail provider that your emails tend to not get delivered. Providers see that as a red flag, meaning bounce rate can have a negative impact on your reputation. There are two types of bounces: soft and hard;
  • A soft bounce is when the email address is valid, and the message reaches the mail server but is not delivered to the recipient's inbox for some reason. For example, the mailbox is full, the message is too big for the inbox, etc.;
  • A hard bounce, on the other hand, means the email address is invalid. That is far more detrimental to your reputation because it tells the mail provider that you are buying your email lists or not taking care of your own. We have a whole article about the downsides of buying and not curating your email lists, and we strongly recommend you check it out;
• Sender History - You can already imagine what this factor entails. Depending on the emails you have sent in the past, you–as the sender–will have a history. Sending too many emails too frequently can be another red flag to an ESP filter. Mail providers want to protect their customers from getting spammed, so moderation is the key here;
• Engagement - Engagement measures how often your emails are interacted with. For example, positive engagement is when users open emails and click on links within them. When users do not open your emails and generally do not engage with them, email providers may send them directly to the spam folder because people do not seem interested. That can have a negative impact on your sender reputation;
• Spam Complaints - We mentioned above how low engagement can send your emails to the spam folder. Your sender reputation will suffer if an ESP thinks you are in any way spamming its customers. That can happen if customers complain about your emails or directly send them to the spam folder: both those things indicate to the ESP that your emails are unwanted;
• Unsubscribe Rates - Finally, if users are massively unsubscribing from your emails, that can also be a red flag for a mail service provider. Again, that shows there is something wrong with your emails, and users do not want them in their inboxes.

There are a lot of things to keep in mind when it comes to improving and preserving your email sender's reputation. At the bottom of it all, however, is moderation. Spam is the most significant way you can ruin your reputation, so a slower cadence of emails is much more preferable than sending message after message. We recently wrote a blog post full of advice for an excellent email marketing strategy, and we discussed this topic extensively.

Additionally, buying an email list is a terrible idea. We mentioned it in the second point of the list above and linked it to a quick article about why that is the case. However, there are a lot of upsides to actually "growing" your own organically. For one, it will be made up of people who want to receive your emails and not a bunch of addresses that may no longer exist or have no idea who you are. Our blog post on the topic goes into great detail, and we recommend you check it out.

Other Ways to Improve Reputation

A good email sender reputation will assure inbox providers that your emails are legitimate and not spam or harmful. That is all obvious. Nobody wants to be marked as a spammer, which can lead to your emails never reaching your subscribers. However, what are some other ways to boost your reputation aside from not spamming and sending quality content? Here is a concise list that should be all you need.

1. Authenticate Your Sending Domain - Unless you use an email service provider (Gmail, Outlook, etc.) to send your emails, you are likely using your private domain. For example, purchasing a domain and hosting from us will let you send emails from that domain. Using a private domain is a good choice since it shows your readers you take your emails seriously by not using an email service provider. However, ensure that the domain is email authenticated. That means enabling SPF, DKIM, and DMARC in that domain. If you are not familiar with those abbreviations, check out our article, which tells you exactly what you need to do. Not only that, but Gmail and Yahoo demand the authentication for bulk senders;
2. Keep an Eye on Analytics - If you are reading this and are concerned about your sender reputation, you likely send many emails to many users. That usually means you are using some sort of a service to facilitate that. Therefore, you have access to analytics. Do not forget to keep an eye on them since they can tell you what needs improvement in your email marketing strategy. Bounce rate, clicks, unsubscribe rate, overall engagement, etc. That information is invaluable to help you identify issues that might potentially harm your sender's reputation;
3. Segment Your Email List - We mention this part in our blog post, but it is vital we do so here as well. Sending all your emails to all your subscribers is not a good idea nowadays. Some of the people on your mailing list might be interested in only a specific type of email over others. They are more likely to send the ones they do not want to spam, which can lead to issues. So, use tactics such as surveys, subscription options, and the analytics from above to segment your email list according to user behavior;
4. Clean Your Email List - Sending emails to dead or uninterested addresses is a huge red flag. That tells email service providers that you are not taking care of your email list and are a spammer. Using your analytics, clean up your mailing list often to ensure only people who want your emails get them.

You can see how things primarily revolve around the cadence of your emails, their content, your mailing list, authentication, and target audience. This general advice should help you maintain a positive sender reputation. However, if you are still experiencing deliverability issues using our email service, feel free to contact us or your marketing platform if you are using one instead.

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