A suppression list (also called a blocklist) is a list of contacts that no one on your Cognism account can find, prospect or export. Admins use it to apply the opt-out records your company already keeps, for example in a marketing automation platform, a compliance tool or a spreadsheet.
- Suppressed contact: a person whose email address is on a suppression list. Cognism matches any email address on their profile, so they stay suppressed if they change role or employer.
- CRM opt-out sync: a separate way to hide opted-out contacts, using opt-out fields synced from your CRM. Suppression lists work alongside it and don't replace it.
Availability: Standard and Pro
Role: Admin (only Admins can create, view and manage suppression lists; the exclusion applies to all users on the account)
Upload a suppression list
Admins upload and manage suppression lists in Settings > Compliance > Suppression List. Contacts are only hidden while Suppression enforcement is turned On at the top of that page.
Suppression lists from Legacy: your existing suppression lists are transferred automatically and show system in the Uploaded by column. Turn Suppression enforcement on so those contacts are hidden from search and prospecting.
Before you start, check your file:
- Format: CSV
- Required column:
email - Optional columns:
first_name,last_name - Limit: up to 100,000 rows per file
- You can upload several lists; a contact on any list stays hidden
To upload a suppression list:
- Go to Settings > Compliance > Suppression List.
- Check that Suppression enforcement is set to On.
- Click Upload suppression list.
- Drop your CSV into the upload area, or click browse to select it.
- Click Upload & suppress.
- Check that the new list appears under Your suppression lists.
Where suppressed contacts are excluded
Suppressed contacts are removed from every place users find, prospect or enrich contacts in Cognism. Users don't see a message saying a contact was suppressed.
| Where | What users see |
|---|---|
| Search | The contact doesn't appear in results. |
| Existing lists | The contact is excluded from the list. |
| Chrome Extension | Contact Data not found |
| CSV enrichment | The record isn't enriched and is missing from the enriched results. |
| CRM Enrichment | The contact doesn't appear in recommendations. |
Only Admins can see or edit suppression lists. Other users can't view, change or bypass them.
Manage and delete a suppression list
The Suppression List page in Settings > Compliance shows how many profiles are suppressed, how many lists are active and when they were last updated. Deleting a list returns its contacts to search and prospecting.
- Your suppression lists: each list shows Uploaded contacts, Profiles suppressed, Uploaded by and Last updated.
- Uploaded contacts vs Profiles suppressed: Uploaded contacts is the number of rows in your file. Profiles suppressed is the number of Cognism profiles that matched, so it can be lower.
- Delete a list: click the bin icon at the end of the list's row. Its contacts are restored to search, lists, the Chrome Extension and enrichment, unless another suppression list or CRM opt-out sync still hides them.
- Pause suppression: turning Suppression enforcement off makes all suppressed contacts visible again until you turn it back on.
How suppression lists work with CRM opt-out sync
Suppression lists and CRM opt-out sync work together. A contact hidden by either one stays hidden in Cognism.
- Without a CRM sync: upload a suppression list, and those contacts are excluded for every user on the account.
- With CRM opt-out sync: keep your sync running and add a suppression list for contacts your CRM doesn't flag. Both apply.
What suppression lists don't cover:
- They don't replace CRM opt-out sync.
- They don't change records already exported from Cognism to your CRM or other tools. Update or remove those records in the system where they now sit.
If suppression lists don't work as expected
| Symptom | Cause | Fix |
|---|---|---|
| Suppressed contacts still appear in search | Suppression enforcement is turned off | Go to Settings > Compliance > Suppression List and turn Suppression enforcement on |
| Contacts from Legacy suppression lists still appear | The lists transferred, but Suppression enforcement is off | Turn Suppression enforcement on |
| The upload fails | The file has more than 100,000 rows, isn't a CSV, or has no email column | Split the file, save it as CSV and include an email column |
| Profiles suppressed is lower than Uploaded contacts | Some emails don't match a Cognism profile | No action needed; only matching profiles can be suppressed |
| A suppressed contact still appears in Cognism | The email on your list doesn't match any email on the contact's Cognism profile | Add the email address Cognism holds for the contact to a suppression list |
| A suppressed contact still appears in your CRM | The record was exported before the contact was suppressed | Update or remove the record in your CRM; suppression lists don't change exported records |
| A user sees Contact Data not found in the Chrome Extension | The contact is on a suppression list or hidden by CRM opt-out sync | Check your suppression lists and CRM opt-out settings |
| A user can't see suppression lists | Suppression lists are Admin-only | Ask an Admin on your account to manage the list |
| A contact reappeared after a list was deleted | Deleting a list restores its contacts | Upload the contacts again to a suppression list |