Sending
Suppression Lists
Suppression lists prevent emails to addresses that have bounced, complained, or unsubscribed.
How Suppression Works
When you send to a suppressed address, the API returns 200 OK but the message is silently dropped.
Suppression Reasons
| Reason | Description | Auto-Removal |
|---|---|---|
bounced | Hard bounce from recipient MTA | Never |
soft_bounced | Temporary failure | After 7 days |
complained | Spam complaint reported | Never |
unsubscribed | Recipient clicked unsubscribe | Never |
manually_added | Manually suppressed via API | Never |
View Suppressions
curl https://api.postmta.com/v1/suppressions -H "Authorization: Bearer pmta_live_xxxx"
curl "https://api.postmta.com/v1/suppressions?reason=bounced" -H "Authorization: Bearer pmta_live_xxxx"Add to Suppression List
curl -X POST https://api.postmta.com/v1/suppressions -H "Authorization: Bearer pmta_live_xxxx" -H "Content-Type: application/json" -d '{"recipients":[{"address":"bad@example.com","reason":"manually_added"}]}'Remove from Suppression List
Re-sending to previously bounced or complained addresses can severely damage your sender reputation.
curl -X DELETE https://api.postmta.com/v1/suppressions -H "Authorization: Bearer pmta_live_xxxx" -d '{"recipients":["bad@example.com"]}'Bulk Upload via CSV
curl -X POST https://api.postmta.com/v1/suppressions/upload -H "Authorization: Bearer pmta_live_xxxx" -F "file=@suppressions.csv" -F "reason=manually_added"