Everything You Need To Know About Email Spam Rate

What is the spam rate?

The email spam rate shows how many emails in one email campaign were marked as spam by recipients or email providers. For example, if you sent 100 emails and 5 of them were marked as spam, your spam rate would be 5%. It’s not a good rate but we’ll talk about that later.

Spam rate is an important metric because once it’s too high, it can harm your sender reputation. That means a threat to your email deliverability in the future — and you want as many people as possible to read your messages!

How are spam complaints made?

Subscribers can mark your message as spam in the email client. After one person marked your email as spam, they won’t see this email in their primary inbox. Also, other messages from the same sender will end up in that recipient’s spam folder by default. Now, let’s look at what this process looks like for the recipient depending on their email client.

If they’re using Gmail, they can simply click on an email they want to mark as spam, and then on the exclamation point icon.

If they’re using Outlook, they can select the email they want to report as spam, right-click on it, and click on Report followed by Report junk.

Factors that influence the email spam rate

Many things can affect your spam rate — for example, how your email authentication is set up, your list hygiene routine, and which email content you send. We’ll discuss these in greater detail later. Here are less obvious factors to consider.

Sending frequency and volume

Sending too many emails too frequently can annoy recipients and lead them to mark your emails as spam. On the other hand, you don’t want to be sending too few emails either — your subscribers may simply forget they’ve ever subscribed to your newsletters or updates! In addition to that, a sudden change in the number of emails you usually send can be a red flag for email providers.

The study by Omnisend suggests that the sweet spot is 10–19 emails per month. However, your clients may have other preferences, so it’s important to keep testing it to see what works best. 

Sender, IP, and domain reputation

Sender reputation is a measure of how trustworthy your email address is based on your past sending behavior. This includes email engagement, spam complaints, and other email data like sending frequency and content quality. A good reputation means your emails are more likely to be delivered to inboxes, while a poor reputation can lead to your emails being marked as spam by servers.

There isn’t one universal sender score that all email providers use but many online tools can help you understand how your emails perform. These include websites like Sender Score, McAfee’s Customer URL Ticketing System, Barracuda Central, and other resources.

The technical infrastructure you’re using to send emails is also crucial. A well-maintained technical setup, including proper email authentication and a dedicated IP, helps ensure your emails are seen as legitimate. If your IP has a bad reputation due to sending spam in the past, email providers are more likely to flag your emails as spam.

Concerned about your IP reputation? You could always try checking if it’s on a blacklist online, for example, run by Spamhaus. If you’re on one, your emails might be blocked or marked as spam. You can check if you’re listed by visiting the Spamhaus website and entering your IP address or domain in their lookup tool. Here’s what it looks like:

Sender and IP reputation aren’t the only reputations you have to worry about if you don’t want your emails to be marked as spam. Domain reputation is important too. It’s how trustworthy your entire domain is (for example, yourcompany.com) based on similar factors and overall email practices. 

Here’s a little explanation of how these reputations intertwine. Let’s say, you have a yourcompany.com domain with 10 sender addresses used for bulk emails and 5 IPs you send from:

• If one IP address out of 5 is blacklisted, the newsletters you send via this IP address (regardless of the sender) will be affected.
• If one sender out of 10 is blacklisted, the newsletters you send using this email address (regardless of the IP address) will be affected.
• If your domain reputation gets worse, all your newsletters (regardless of the IP or the particular email address) will be affected.

How to check spam rates

So, now you know what the process looks like for the recipient of an unwanted email. But what if you were the one who sent it?

Using an ESP

In general, if you’re using an email service provider, you should have access to all the relevant statistics like open rate, bounce rate, and spam complaints. Make use of these analytics to see whether subscribers find your content engaging and if there are any problems with deliverability. 

Here’s where to find the spam complaint info in Selzy’s analytics dashboard:

Pro tip: check the bounce reports — they include info about spam complaints too. For example, in the image above, the dashboard indicates that one of the undelivered emails was rejected as spam.

Feedback loops

Feedback loops (FBLs) for email spam are reports provided by Gmail and some other email clients. These reports notify senders when their emails are marked as spam by recipients who use the same email client as you do. So, if you use Gmail, your FBL reports will only contain the data about spam complaints made in Gmail. When a recipient reports your email as spam, the feedback loop sends this information back to you, allowing you to identify and remove those subscribers from your list.

The format of the feedback you’ll get from an FBL depends on the service you’re using. For example, Gmail offers aggregated data about the performance of your email rather than individual spam reports. In Gmail, you can find FBL reports on your Postmaster dashboard.

FBLs aren’t enabled by default — if you want to use this feature, you need to set it up. The setup and implementation process varies between email providers.

What is a bad spam complaint rate?

A high spam complaint rate is generally considered to be above 0.1%, which means more than 1 out of every 1,000 emails you send is marked as spam. This is an industry benchmark set by major email clients like Gmail. According to Google, your spam rate should never reach 0.3%.

I’m willing to bet this guy’s spam rates exceed 0.3%:

How high spam rates affect the email sender

Let’s consider some of the ways you, as an email sender, may be affected by high spam rates:

• Damaged sender reputation and reduced deliverability. You already know that your sender reputation and spam rate are intrinsically linked. A high spam rate damages your reputation because email providers see it as a sign that people don’t want your emails, leading them to block or mark your future emails as spam. This leads to the decreasing deliverability of your emails.
• Potential legal compliance consequences. A high spam rate may have potential legal consequences as it can indicate that you’re sending unsolicited emails or not following legal requirements. Such actions may violate anti-spam laws like the CAN-SPAM Act in the US and GDPR in Europe. This can lead to fines and penalties for sending unsolicited or unwanted emails — even if your emails aren’t actually unsolicited!
• Loss of customer trust. A high spam rate can cause a loss of customer trust. For example, if your spam rate is high, your emails will land in spam folders automatically. This may leave your subscribers concerned about your reputation — and they’ll unsubscribe from your emails due to distrust.

6 ways to lower spam rate and avoid complaints

We hope we’ve managed to impress the seriousness and the importance of spam rates on you! Want to make sure your emails aren’t perceived as spam either by email clients or the recipients, and to increase your deliverability? Follow our checklist of best practices below.

Implement robust email authentication

You already know that email authentication protocols are important in lowering the spam rate. Therefore, email authentication can lower spam rates by verifying that your emails are legitimate and from a trusted source. This helps prevent your emails from being flagged as spam.

This is important for email marketing and helps email clients tell the difference between real and fake emails. By verifying emails, these protocols protect users from scams and keep their personal information safe, ensuring only genuine messages get through and blocking fake ones. Authentication protects you from domain spoofing as well!

Robust email authentication involves using methods like SPF, DKIM, and DMARC. These tools check and confirm your email’s authenticity.

Clean your email list regularly

Email list hygiene is the process of keeping your email list clean by removing inactive or invalid addresses. This helps improve deliverability and engagement, ensuring your emails reach real, interested recipients, and reducing your email spam rate.

Inactive or invalid email contacts can lead to more bounces. This, in turn, signals to email providers that your emails might be unwanted. So, timely management of email lists helps lower spam rates, making it one of the most important email practices! Luckily, keeping your email lists squeaky clean is a lot easier with Selzy’s list hygiene feature. It allows you to quickly remove the deadweight of useless contacts. Check out our Help Center to learn how.

As far as email lists are concerned, here’s another helpful tip — as tempting as it may be, you should never buy email lists. In bought lists, recipients gave no consent to your emails, so they will likely mark your messages as spam. Besides, some of these email addresses may no longer be valid.

Use double opt-in for subscriptions

There are two ways to subscribe customers to your emails: single and double opt-in. Single opt-in means that when someone signs up for your email list, they are added straight away. Double opt-in means that the subscriber needs to confirm their subscription by clicking a link sent to their email address — and only after that they’re added to the list.

In general, double opt-in is more reliable — it ensures that the email address is valid and that the subscriber really wants to receive your emails, thus lowering spam rates. In addition to this, your opens and clicks will be higher too.

You’ve probably received one or two subscription confirmation emails in your life but here’s an example of what these look like:

Personalize and segment your emails

Personalization and segmentation are always a good idea for email marketers but did you know that these practices can also lower your spam rate?

Email personalization is customizing your emails to include information specific to each recipient, such as their name or interests. This makes the recipient more likely to open the emails and less likely to mark them as spam, as they feel more relevant and engaging.

For example, this email from Netflix offers personalized recommendations based on the subscribers’ recently watched movies.

Email segmentation, on the other hand, is tailoring email content for groups, not individuals. It’s dividing your email list into smaller groups based on different criteria like interests, location, or behavior. This allows you to send more targeted and relevant emails to each group, improving engagement and effectiveness and reducing the likelihood of the recipient marking your email as spam.

Monitor your sender reputation

Sender reputation is vital when it comes to lowering spam rates. So, keeping track of it makes sense — and here’s how you can do that.

• Checking ESP reports. We mentioned that already — be sure to continuously track all the relevant analytics in your ESP’s dashboard. Don’t just look at spam rates but also engagement metrics like opens and clicks.
• Monitoring feedback loops. Similarly to ESP reports, watch out for increases in spam complaints from recipients.
• Monitoring blacklists. A sudden drop in email delivery rates may indicate that your domain or IP address has been blacklisted. There are several online resources, such as MxToolbox, where you can check if that’s the case.

Optimize email content and design

As an email marketer, you know that producing high-quality and relevant content is crucial to the effectiveness of an email marketing campaign. However, did you know it also affects email spam rates? 

High-quality, relevant content is less likely to be marked as spam as it’s valuable to the recipient. On the other hand, poor content quality can lead to more spam complaints and reduced engagement, increasing the chances of your emails being marked as spam. 

For example, if the recipient doesn’t open your emails over time, their email provider may start marking them as spam. This is because low engagement, like not opening emails, signals that the content might not be relevant or wanted. 

Here are a few ideas on what you can do with the emails themselves to optimize them and lower those spam rates.

• Build a clear layout. Use a clean and organized design that is easy to read and visually appealing. Building visually engaging emails can be pretty time-consuming, so consider using email templates.
• Avoid spammy words. Steer clear of phrases that might trigger spam filters, such as “free” or “act now.” Other email spam words include  “OPEN!” and “exclusive access” either in the main body of the email or the subject line.
• Ditch image-only emails. Email providers frequently flag these types of emails because they can’t easily analyze the content for spammy keywords or phishing attempts. Without text, it’s harder for spam filters to determine if the email is safe.
• Use a proper sender name. Use a consistent and familiar sender name to build trust with your subscribers.
• Don’t shorten your links. Shortened links in emails can lead to them being marked as spam. Spam filters may see short links as suspicious because they can hide the true destination, which is a tactic frequently used by spammers. To avoid this, use full URLs or branded links that clearly show the “destination”.
• Unsubscribe button. It’s mandatory to include an unsubscribe button in marketing emails, as laws like the CAN-SPAM Act and GDPR require that recipients have a clear and easy way to opt out of receiving future emails.

Conclusion

We hope we’ve answered all the questions you may have had about email spam rates! Here are some takeaways to remember:

• The spam rate shows how many emails were marked as spam automatically by your subscribers. You can check this metric in your ESP or using feedback loops provided by email clients.
• The zero spam rate is somewhat inevitable but be concerned if it’s above 0.1% or suddenly increases.
• There are many ways to keep your spam rates low from cleaning your contact lists to properly setting up email authentication. We covered all that in our anti-spam checklist for email marketers — check it out if you want to learn more!