# How suppression works with campaigns

> Suppression is workspace-wide, not per campaign or per project. An opt-out holds across every campaign and every mailbox in the workspace, including campaigns…

Source: https://warmerly.com/docs/suppression/how-suppression-works-with-campaigns

Suppression is **workspace-wide**, not per campaign or per project. An opt-out holds across every campaign and every mailbox in the workspace, including campaigns you create later.

Warmerly checks the recipient right before each email is sent, so an address added a second ago is already honoured. A suppressed lead is not sent to: its status becomes **Unsubscribed** or **Unavailable mailbox** depending on why the address is listed, and its sequence stops. Importing the same address again into another campaign does not bypass the list.

Verification is separate. [Email verification](https://warmerly.com/docs/verify) checks whether an address can receive mail, and does not read or change the suppression list. Verify lists before you import them to keep bounces low, and rely on the list to honour opt-outs.

## More from Suppression

- [The list is write-only](https://warmerly.com/docs/suppression/the-list-is-write-only): POST /suppression is the only customer-callable endpoint on this resource. Adding an address works with your…
- [Add addresses](https://warmerly.com/docs/suppression/add-addresses): Requires X-Api-Key. Not project-scoped. The list applies to a whole workspace, not a single project. The…
- [Other ways to add addresses](https://warmerly.com/docs/suppression/other-ways-to-add-addresses): Other ways to add addresses in the Warmerly Suppression API reference.