# Suppression Lists and Subscriber Status > Suppression protects people who should not receive normal marketing email, such as unsubscribed, bounced, or complained subscribers. - Human page: https://mailrith.com/guides/suppression-lists - Markdown page: https://mailrith.com/guides/suppression-lists.md - Category: Authentication and Deliverability - Reading time: 4 min read - Related keywords: Suppression Lists and Subscriber Status, Suppression Lists and Subscriber Status guide, Authentication and Deliverability, Authentication and Deliverability guide, email sending guide, email marketing guide, email deliverability guide, Subscribers ## 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 free tool, pair the tool result with the relevant issue or step section from this guide. ### Suppression Lists and Subscriber Status Suppression protects people who should not receive normal marketing email, such as unsubscribed, bounced, or complained subscribers. A suppression list is a safety list. It keeps certain addresses out of future sends even if they match a subscriber rule. In Mailrith, subscriber status plays this protective role. For example, a subscriber might have the `customer` tag and match a segment, but if they unsubscribed or complained, they should not receive normal marketing email. This protects subscribers and the sender. It also prevents accidental resends to people who already gave a clear signal. Think of suppression as a final safety gate after targeting. Tags and segments decide who you want to reach. Subscriber status decides who is safe to send to. A person can match the subscriber rule and still be blocked from a normal marketing send. Suppression exists because subscriber rules are not enough. A broad segment like `all customers` may include people who unsubscribed, hard bounced, complained, or were manually blocked. The safety state should win over the targeting rule. Suppression also protects future deliverability. Repeatedly sending to bounced addresses or people who complained can hurt [Sender Reputation and Spam Rate](https://mailrith.com/guides/sender-reputation-and-spam-rate.md). Do not treat suppression as an error just because the final recipient count is smaller than the segment count. It often means Mailrith is correctly protecting people who should not receive normal marketing email. 1. Before sending, define the target subscribers with tags or segments. 2. Let Mailrith exclude subscribers whose status should not receive normal marketing email. 3. After imports, do not mark old unsubscribed, bounced, or complained contacts as active. 4. If a subscriber says they did not receive an email, check their subscriber status before changing the campaign. 5. If you must reactivate someone, confirm the subscriber asked for it and document why the status changed. 6. When troubleshooting a send count, compare the segment size with the final eligible recipient count. 7. Review [Bounces](https://mailrith.com/guides/bounces.md), [Spam Complaints](https://mailrith.com/guides/spam-complaints.md), and [One-Click Unsubscribe and Opt-Outs](https://mailrith.com/guides/one-click-unsubscribe.md) so you understand why statuses change. - Respect unsubscribed, bounced, complained, blocked, and similar protected states. - Do not import old unsubscribed addresses as active subscribers. - Check subscriber status when a person expected an email but did not receive it. - Use workspace-specific review before manually changing protected statuses. - Keep test contacts clearly labeled so they do not pollute real subscriber decisions. - Suppression protects sender reputation by reducing repeated bounces and complaints. - If you are troubleshooting delivery, check suppression before assuming your email delivery service failed. - A subscriber can match a tag or segment and still be excluded because their status is not safe for marketing email. - Reactivation should be rare and based on the subscriber's clear request, not a desire to increase campaign count. ## Fix Common Issues ### Keep Invalid Addresses Out A list checker found invalid addresses that are likely to bounce or fail before sending. 1. Export the clean rows from the list checker. 2. Do not import invalid rows into an active list. 3. Keep a separate cleanup file if you need to contact the source owner or fix typos manually. 4. Do not reactivate bounced or invalid contacts unless the person confirms the corrected address. 5. After importing the clean list, send first to a smaller engaged segment if the source is old or uncertain. > If the subscriber count drops at send time, check subscriber status before assuming the segment is broken. The final count may be lower because Mailrith is protecting suppressed contacts. Related resources: - [Subscribers](https://mailrith.com/docs/subscribers.md): Review subscriber status, profile data, and activity history. ## Related Guides - [Sender Domains and Email Authentication](https://mailrith.com/guides/sender-domains-and-authentication.md): Your sender domain is the name inboxes learn to trust, and authentication proves that your email delivery service is allowed to send for it. - [From, Reply-To, and Return-Path](https://mailrith.com/guides/from-reply-to-and-return-path.md): An email has several sender-related addresses, and each one has a different job in delivery and replies. - [DNS, PTR, and Reverse DNS](https://mailrith.com/guides/dns-and-reverse-dns.md): DNS records identify your domain, while reverse DNS helps inboxes check whether a sending IP has a sensible hostname.