When people receive an email they do not want, they may mark it as spam. If enough recipients do this, mailbox providers can start treating the sender as less trustworthy. This is where spam complaint rate becomes an important email deliverability metric.<\/p>\n\n\n\n
Your spam complaint rate indicates how often recipients mark your emails as spam. A rising rate can indicate issues with your email list, content, sending frequency, or subscriber expectations. It can also affect how mailbox providers handle future messages from your domain.<\/p>\n\n\n\n
But what counts as a high spam complaint rate? How do you calculate it? And what can you do if too many people are marking your emails as spam?<\/p>\n\n\n\n
This guide explains what the spam complaint rate means, what a healthy rate looks like, how to measure it, and practical ways to reduce it.<\/p>\n\n\n\n
Spam complaint rate is the percentage of delivered emails that recipients mark as spam. The basic spam complaint rate formula is:<\/p>\n\n\n\n
Spam Complaint Rate = Spam Complaints \u00f7 Emails Delivered \u00d7 100<\/em><\/p>\n\n\n\n For example, if you deliver 50,000 emails and receive 25 spam complaints:<\/p>\n\n\n\n 25 \u00f7 50,000 \u00d7 100 = 0.05%<\/p>\n\n\n\n Your spam complaint rate is therefore 0.05%.<\/p>\n\n\n\n It is worth keeping this metric separate from other email metrics. Your bounce rate tells you how many emails could not be delivered, while your unsubscribe rate shows how many people chose to stop receiving your emails. A spam complaint is different because the recipient is telling their email provider that they no longer want to receive your emails.<\/p>\n\n\n\n Mailbox providers can use these complaints as a signal when deciding how to treat your future emails. Gmail, for example, tracks spam rates through Google Postmaster Tools. It looks at the percentage of messages delivered to engaged Gmail recipients that they then mark as spam.<\/p>\n\n\n\n One thing to keep in mind is that your spam complaint rate does not tell you how many of your emails Gmail automatically sends to the spam folder.<\/p>\n\n\n\n For example, if Gmail is already sending a large number of your emails straight to spam, recipients may never see those emails in their inboxes. They cannot mark an email as spam if they never see it there. This means your reported spam rate could look low even when your inbox placement is not great.<\/p>\n\n\n\n So, don’t look at spam complaint rate in isolation. It is one piece of the bigger deliverability picture, along with things like bounce rates, email engagement, authentication, list quality, and sending habits.<\/p>\n\n\n\n Keeping an eye on this number can help you spot problems early, especially when your complaint rate suddenly starts going up.<\/p>\n\n\n\n There is no single average spam complaint rate for emails that applies to every sender. The rate can vary depending on your industry, audience, email type, and the mailbox providers you send to. So, rather than comparing your rate with a general industry average, it is more useful to look at the recommendations set by the mailbox providers your subscribers use.<\/p>\n\n\n\n For Gmail, Google recommends keeping your user-reported spam rate below 0.1% and avoiding a rate of 0.3% or higher.<\/p>\n\n\n\n Here is what these numbers mean:<\/p>\n\n\n\n Google calculates spam rates daily, and you can monitor this data through Google Postmaster Tools. One important point to remember is that 0.3% should not be treated as an acceptable average spam complaint rate. It is better understood as a threshold that senders should stay well below.<\/p>\n\n\n\n For example, if you send 100,000 emails:<\/p>\n\n\n\n Three hundred complaints may not sound like much when compared with 100,000 emails, but mailbox providers can use recipient feedback as one of the signals when evaluating your sending behavior.<\/p>\n\n\n\n So, instead of focusing on whether the spam complaint rate is average, focus on whether it is low enough for the mailbox providers you send to and whether it is improving or getting worse over time.<\/p>\n\n\n\n It is also important to watch how your rate changes over time. For example, a jump from 0.02% to 0.08% still keeps you below Google’s 0.1% recommendation, but it could be an early sign that something has changed in your email program.<\/p>\n\n\n\n Spam complaint rate is not something you should check only when email delivery starts having problems. Track it regularly so you can spot changes early. For Gmail, you can use Google Postmaster Tools to monitor spam rate and other delivery signals. A rising rate can point to issues with your email list, content, or sending practices.<\/p>\n\n\n\n However, a low spam rate does not always mean your emails are reaching the inbox. If Gmail is already sending many of your emails to spam, fewer recipients will see them in their inbox and mark them as spam. Your reported rate may look low even when inbox placement is poor.<\/p>\n\n\n\n Google also notes that it can take up to seven days for spam rates to return to normal after you make improvements. For Gmail, aim to keep the spam rate below 0.1% rather than treating 0.3% as an acceptable level.<\/p>\n\n\n\n If your rate starts rising, review your list, sending frequency, content, and recent campaigns. For Gmail authentication issues, see EasyDMARC’s \u2018550-5.7.26 Gmail Error: What is it? How to Solve it\u2019<\/a> guide for more details.<\/p>\n\n\n\n A high spam complaint rate usually means that some recipients do not consider your messages relevant, expected, or wanted. However, this does not necessarily mean the emails are malicious or that your subscribers never opted in. Even legitimate email programs can generate complaints when expectations and actual sending behavior do not match.<\/p>\n\n\n\n Here are some of the most common causes:<\/p>\n\n\n\n When recipients do not clearly remember subscribing to your emails, they are more likely to report them as spam. This can happen when signup forms are unclear, consent is bundled with another action, or email addresses are collected through sources where people did not explicitly expect ongoing communication.<\/p>\n\n\n\n The problem can also arise when a legitimate subscriber is added to several different mailing lists without clearly understanding what each list is for. A clear opt-in process should tell people what they are signing up for, what type of content they will receive, and, where relevant, how often they can expect it. This sets the right expectation before the first email arrives.<\/p>\n\n\n\n Subscribers may be happy to receive your emails once a week but become frustrated when the frequency suddenly increases to several messages a week. This is especially common during product launches, holiday promotions, or sales campaigns, when marketers increase their sending volume without considering how the audience normally interacts with their emails.<\/p>\n\n\n\n Frequency also becomes a problem when different teams send emails independently. A subscriber might receive a newsletter, a promotional campaign, a product update, and an automated recommendation within a few days, even though each team considers its own message reasonable. A coordinated sending schedule can prevent subscribers from feeling overwhelmed and reduce the chance that they use the spam button to stop the flow.<\/p>\n\n\n\n People generally have a reason for giving a business their email address. They may want product updates, educational content, discounts, event invitations, or information about an order. When the content gradually moves away from that original expectation, recipients may start treating otherwise legitimate emails as unwanted.<\/p>\n\n\n\n For example, someone who signs up for cybersecurity tips may not expect frequent sales emails from the same company. The address is valid, the subscriber did opt in, and the emails may be professionally written, but the content no longer matches the reason the person subscribed. Keeping email content aligned with subscriber interests and using segmentation can help prevent this mismatch.<\/p>\n\n\n\n An email address does not remain equally valuable forever. People change jobs, abandon old inboxes, switch interests, or simply stop wanting updates from a company. If these subscribers remain on your active mailing list indefinitely, they may eventually become disengaged enough to report an email as spam.<\/p>\n\n\n\n The problem is particularly easy to miss with large databases because inactive subscribers may make up only a small percentage of the overall list. However, repeatedly sending to people who have not opened or interacted with your emails for a long time can weaken overall engagement. Regularly reviewing inactive segments and using re-engagement campaigns or suppression rules can help keep your active audience healthier.<\/p>\n\n\n\n This is a less obvious problem, especially for companies with long customer journeys. Someone may willingly subscribe to your emails today and still report one of them as spam several months later simply because they no longer remember giving you permission.<\/p>\n\n\n\n This can happen when there is a long gap between signup and the first meaningful email, or when a company sends very infrequently and then suddenly resumes regular campaigns. A useful way to prevent this is to maintain a consistent communication pattern and make the connection between the signup and each email clear. Welcome emails can also reinforce what the subscriber signed up for and what they can expect going forward.<\/p>\n\n\n\n Larger email programs often use different subdomains, email addresses, or sending platforms for different types of communication. From an internal perspective, this may make perfect sense. From the recipient’s perspective, however, the messages can appear to come from completely different senders.<\/p>\n\n\n\n For example, someone may subscribe to updates from Company A, then later receive promotional emails from a different subdomain or brand name that they do not immediately recognize. Even though the same organization is behind both messages, the unfamiliar sender identity can make the email look unexpected. Keeping sender names, branding, and communication preferences consistent helps recipients recognize why they are receiving a message and who it is from.<\/p>\n\n\n\n Reducing your spam complaint rate is not just about sending fewer emails. The real goal is to ensure the right people receive the right emails and understand why they are receiving them. Here are practical ways to reduce your rate:<\/p>\n\n\n\n Your email list should be made up of people who have clearly agreed to receive your emails. Avoid buying lists or adding addresses collected for a different purpose unless you have a valid basis for sending them the specific type of email you plan to send.<\/p>\n\n\n\n Your signup form should also make the purpose of the subscription clear. Tell people what kind of emails they will receive and, where relevant, how often they can expect them. A confirmed opt-in process can add another layer of protection by asking subscribers to confirm that they own the address and want to receive your emails. This can help prevent accidental signups and keep your list more engaged from the beginning.<\/p>\n\n\n\n Some people will eventually decide they no longer want your emails. That is normal, even if they originally signed up willingly. The problem starts when there is no easy way for them to leave your list. So, always keep the unsubscribe option easy to find and make the process simple. Recipients should not have to log in, fill out a long form, or click through several pages just to stop receiving marketing emails. When unsubscribing is difficult, some people may use the spam button instead.<\/p>\n\n\n\n For Gmail bulk senders, Google also requires one-click unsubscribe for marketing and promotional messages. Making the process simple gives subscribers a clear way to leave without reporting your emails as spam.<\/p>\n\n\n\n An email list needs regular maintenance. Some subscribers will become inactive over time, while others may no longer use the address they signed up with. Keeping every address on your active list forever can make it harder to understand how engaged your audience really is.<\/p>\n\n\n\n Start by identifying subscribers who have not opened or interacted with your emails for a long period. You can send a re-engagement campaign asking whether they still want to hear from you. If they do not respond, consider suppressing them from future campaigns. Removing inactive contacts may reduce your total list size, but it can give you a more engaged audience and a clearer picture of how your emails are performing.<\/p>\n\n\n\n Subscribers should have a reasonable idea of how often they will hear from you. If someone signs up for a weekly newsletter and suddenly starts receiving emails every day, the change can quickly become frustrating.<\/p>\n\n\n\n Try to keep your sending frequency close to what you promised when people subscribed. If you need to increase the frequency for a campaign or seasonal promotion, consider letting subscribers choose how often they want to hear from you. For example, you could offer daily, weekly, or monthly communication preferences. Giving people some control can reduce the chances of them feeling overwhelmed by your emails.<\/p>\n\n\n\n Sending the same email to your entire database may be convenient, but it does not mean every subscriber will find the message useful. Different people join your list for different reasons, and their interests can change over time.<\/p>\n\n\n\n Use information such as interests, previous purchases, engagement, location, or the type of content someone signed up for to create relevant segments. You can then send different messages to different groups instead of treating your entire database as one audience. The more closely an email matches what a subscriber expects, the less likely they are to see it as unwanted.<\/p>\n\n\n\n Your overall spam complaint rate can tell you that there is a problem, but it may not tell you where the problem started. A better approach is to compare complaint rates across individual campaigns and subscriber groups.<\/p>\n\n\n\n Look at factors such as campaign, audience segment, email type, acquisition source, sending frequency, date, or time period<\/p>\n\n\n\n For example, if your regular newsletter has a low complaint rate but a recent promotional campaign generated significantly more complaints, the campaign itself may need closer attention. Looking at the data this way helps you find patterns that can easily disappear inside an overall account-level average.<\/p>\n\n\n\n Email authentication<\/a> does not stop a recipient from clicking the “Report spam” button, but it is still an important part of a healthy email program. Proper authentication helps mailbox providers verify that your messages are actually coming from an authorized sender.<\/p>\n\n\n\n SPF<\/a> identifies the servers allowed to send email on behalf of your domain. DKIM<\/a> adds a cryptographic signature that helps verify that a message came from an authorized source and was not changed in transit. DMARC<\/a> builds on SPF and DKIM by allowing domain owners to set policies for messages that fail authentication and receive reports about email using their domain.<\/p>\n\n\n\nWhat is an Average Spam Complaint Rate for Emails<\/strong><\/h2>\n\n\n\n
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How to Monitor Spam Complaint Rate Over Time<\/strong><\/h2>\n\n\n\n
What Causes a High Spam Complaint Rate?<\/strong><\/h2>\n\n\n\n
Sending to People Who Did Not Clearly Opt In<\/strong><\/h3>\n\n\n\n
Sending Emails Too Frequently<\/strong><\/h3>\n\n\n\n
Sending Content That Does Not Match Subscriber Expectations<\/strong><\/h3>\n\n\n\n
Continuing to Email Old or Inactive Subscribers<\/strong><\/h3>\n\n\n\n
Making Subscribers Forget Why They Signed Up<\/strong><\/h3>\n\n\n\n
Using Multiple Sending Identities Without a Clear Subscriber Experience<\/strong><\/h3>\n\n\n\n
How to Reduce Your Spam Complaint Rate<\/strong><\/h2>\n\n\n\n
Send Emails Only to People Who Have Given Permission<\/strong><\/h3>\n\n\n\n
Make it Easy to Unsubscribe<\/strong><\/h3>\n\n\n\n
Keep Your Email List Clean<\/strong><\/h3>\n\n\n\n
Set a Clear and Consistent Sending Schedule<\/strong><\/h3>\n\n\n\n
Send More Relevant Emails Through Segmentation<\/strong><\/h3>\n\n\n\n
Find Out Which Campaigns Are Generating Complaints<\/strong><\/h3>\n\n\n\n
Keep SPF, DKIM, and DMARC Properly Configured<\/strong><\/h3>\n\n\n\n