Block hard bounces and honor opt-outs to protect your sender reputation.
Stop maintaining custom blocklists or accidentally emailing unsubscribed users on a retry. Bird automatically blocks repeat sends to hard-bounced and complained addresses while keeping marketing opt-out preferences separate, so someone who unsubscribes from your newsletter still receives critical password resets and order receipts.
Recipient protection
Example record
Hard bounces suppress all email. Complaints suppress non-transactional email. Unsubscribe preferences are stored separately.
Keep bad addresses from hurting your inbox placement.
Repeatedly mailing invalid addresses or people who marked a campaign as spam quickly damages your domain reputation at Gmail, Outlook, and Yahoo. Because suppression is built into the Bird Email API, permanent bounces stop future sends automatically, and spam complaints halt promotional mail without blocking password resets or order confirmations. When a customer asks why an email did not arrive, your support team can trace the rejection back to the exact message and bounce diagnostic that triggered it.
Built-in list hygiene without custom blocklist code.
Protect your sender score automatically, keep transactional mail flowing, and stay in sync with your database.
- 01
Automatic protection on hard bounces and complaints.
When an address hard-bounces or a recipient reports spam, Bird records the suppression immediately and blocks repeat sends before they leave the platform. Temporary soft bounces and mailbox-full deferrals retry normally without permanently blocking the recipient.
- 02
Transactional emails still reach unsubscribed users.
Newsletter unsubscribes and spam complaints stop promotional campaigns without blocking transactional sends. A customer who opts out of marketing announcements still receives password resets, login codes, and order receipts.
- 03
Import existing blocklists when you migrate.
Bring your existing suppression list from SendGrid, Amazon SES, Mailgun, or Resend through the dashboard, API, or CLI so you do not re-email known invalid addresses on day one.
- 04
Inspect and clear recovered addresses safely.
When a recipient fixes a misconfigured domain or DNS issue, inspect the original bounce reason and source message before removing the record. Separate opt-out preferences stay intact even if you clear a bounce suppression.
- 05
Sync changes to your app with webhooks and APIs.
Receive a webhook event whenever a suppression is created, or query and filter records by email address or reason through the REST API, SDKs, CLI, and MCP so your CRM and internal tools reflect the latest recipient status.
Investigate missing emails and manage your blocklist from the CLI or API.
Day-to-day bounce and complaint protection runs automatically without manual upkeep. When a customer contacts support about a missing email or your team migrates from another provider, you can look up an address, filter records by bounce or complaint reason, add known bad addresses, or remove a resolved bounce through the REST API, SDKs, or the Bird CLI. Support tools and AI coding assistants can also check whether a recipient is suppressed directly over Bird MCP.
# Look up why an address is on the list.
$ bird email suppressions list --email ada@example.com \
| jq -c '.data[] | {id, reason, applies_to}'
{"id":"sup_01krdgeqcxet5s7t44vh8rt9mg","reason":"hard_bounce",
"applies_to":"all"}
# Reinstate one that recovered, by record id.
$ bird email suppressions remove sup_01krdgeqcxet5s7t44vh8rt9mg --yes
How Bird separates delivery blocks from marketing opt-outs.
Permanent bounces and manual blocklist entries stop both transactional and marketing sends. Spam complaints and unsubscribe preferences block promotional campaigns while allowing critical transactional emails like password resets and receipts through.
| Reason | Triggered by | Blocks |
|---|---|---|
| Hard bounce | Permanent delivery failure to an invalid or non-existent address | Blocks transactional and marketing email |
| Spam complaint | Recipient marks an email as spam in their mailbox | Blocks marketing email; allows transactional receipts and resets |
| Manual suppression | Added by your team via the dashboard, API, or CLI | Blocks transactional and marketing email |
Explore the developer guides.
Follow the suppressions guide to query the blocklist, handle rejection webhooks, and test suppressed sends in the sandbox, or read the deliverability guide to configure domain authentication, IP warmup, and one-click unsubscribe headers.
Questions about email suppressions
Which recipients are suppressed automatically?
Is an unsubscribe a suppression?
Can I remove or test a suppression?
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