# Spam Complaints > A complaint means a subscriber marked your email as spam. Inbox providers treat complaints as one of the strongest negative signals. - Human page: https://mailrith.com/guides/spam-complaints - Markdown page: https://mailrith.com/guides/spam-complaints.md - Category: Authentication and Deliverability - Reading time: 4 min read - Related keywords: Spam Complaints, Spam Complaints guide, Authentication and Deliverability, Authentication and Deliverability guide, email sending guide, email marketing guide, email deliverability guide, One-Click Unsubscribe and Opt-Outs, Permission and Compliance, Sender Reputation and Spam Rate ## AI Agent Notes - Use this page as plain-language guidance for the specific email sending issue named in the title. - Preserve the distinction between Mailrith, an email delivery service, DNS, and inbox providers when explaining fixes. - When a user is running a Mailrith free tool, pair that specific free-tool result with the relevant issue or step section from this guide. ### Spam Complaints A complaint means a subscriber marked your email as spam. Inbox providers treat complaints as one of the strongest negative signals. A spam complaint is not the same as an unsubscribe. A complaint tells the inbox provider that the subscriber believes the message should not have been in their inbox. Complaints can happen when permission was weak, the sender identity was unclear, the content was irrelevant, the sending frequency was too high, the subject line was misleading, or an old list no longer remembers signing up. A complaint is one of the strongest negative signals because it comes directly from the subscriber. Inbox providers can use complaint patterns to decide whether to trust future email from the same sender. A low complaint percentage can still be important on a large send. For example, a small percentage of a large subscriber list can still mean many people told the inbox provider that the mail was unwanted. Complaints are not only a content problem. They can also be a promise problem. If a person signed up for product updates and receives unrelated promotions every day, the email may feel like spam even when the design is clean. Treat complaints as a serious signal. If complaints increase, pause before the next campaign and check the subscribers, subscriber source, message, sender identity, and sending frequency. 1. Make sure your email delivery service complaint or spam-report webhooks are connected to Mailrith. 2. After each send, review the complaint count together with unsubscribes and bounces. 3. If complaints increase, identify which subscriber source was used for the campaign. 4. Check whether the subject line or sender name could have made subscribers expect a different message. 5. Check whether the campaign was sent to subscribers who had not opened or clicked in a long time. 6. Check whether the unsubscribe link was visible and easy for subscribers to use. 7. While you fix the cause, send future campaigns to more engaged subscribers first. 8. Do not keep mailing subscribers who complained. Let [Suppression Lists and Subscriber Status](https://mailrith.com/guides/suppression-lists.md) protect them. - Do not send email to people who did not ask for it. - Use a sender name that subscribers recognize. - Use honest subject lines. - Make unsubscribing easy so subscribers do not use the spam button to leave. - Review complaint patterns by subscriber source and campaign type. - A small number of complaints can matter on a large send, so do not ignore complaint percentages. - High complaints usually point to a subscriber or permission problem, not a button color problem. - A sudden complaint spike after an import usually means the list source or permission was weak. - A complaint spike from active subscribers usually means the content, frequency, or sender promise changed. - If complaint webhooks are missing, Mailrith may not know which subscribers need protection. > When complaints increase, do not send a bigger campaign to make up for it. Reduce risk, find the cause, and send the next campaign to the most engaged subscribers first. Related resources: - [One-Click Unsubscribe and Opt-Outs](https://mailrith.com/guides/one-click-unsubscribe.md): Make leaving easy so subscribers do not use the spam button. - [Permission and Compliance](https://mailrith.com/guides/permission-and-compliance.md): Send only to people who expect your email. - [Sender Reputation and Spam Rate](https://mailrith.com/guides/sender-reputation-and-spam-rate.md): Understand how complaints affect future delivery. ## Related Guides - [Sender Domains and Email Authentication](https://mailrith.com/guides/sender-domains-and-authentication.md): Your sender domain is what inbox providers learn to trust. Authentication proves that your email delivery service is allowed to send email for your domain. - [From, Reply-To, and Return-Path](https://mailrith.com/guides/from-reply-to-and-return-path.md): An email can include several sender-related addresses. Each address has a separate role for delivery, authentication, or replies. - [DNS, PTR, and Reverse DNS](https://mailrith.com/guides/dns-and-reverse-dns.md): DNS records identify your domain. Reverse DNS helps inbox providers check that a sending IP address has a valid hostname.