Not every contact on a target list should receive outreach. Some have previously asked not to be contacted. Some are existing customers. Some are in a legal jurisdiction with strict opt-out requirements. Sending to any of them is not just bad practice. It can damage your reputation, trigger complaints, and in some cases create legal exposure.
The suppression layer is what prevents that from happening.
What suppression means in practice
Suppression is the process of cross-referencing every contact list against a set of exclusion criteria before any outreach begins. Any contact that matches a suppression rule gets removed from the active list automatically.
This happens before the first send and continues on an ongoing basis as new contacts are added to campaigns and as new suppression signals come in.
What we suppress
We maintain suppression lists across four categories.
Opt-outs and unsubscribes cover anyone who has previously replied asking to be removed, clicked an unsubscribe link, or been manually marked as do not contact across any of your previous campaigns. Once a contact is on the opt-out list they never receive outreach from your campaigns again regardless of which list they appear on.
Existing customers are suppressed by default. There is no value in sending cold outreach to someone who is already paying you. We cross-reference your contact lists against your CRM data and remove any current customers before sequences go live.
Active pipeline contacts are people already in your sales process. Sending them a cold outreach sequence while a conversation is already in progress creates confusion and can undermine an active deal. We suppress these contacts and flag them so your sales team knows they are being worked separately.
Competitor and sensitive accounts cover any companies or individuals you specifically want to exclude. This might include direct competitors, press contacts, investors, or anyone else where unsolicited outreach could cause a problem. We build a custom exclusion list based on your input during onboarding.
How the suppression check works
Every contact on an incoming list gets checked against all four suppression categories before they are activated. This happens automatically as part of the list build process.
Any contact that matches a suppression rule gets flagged rather than deleted. We keep a record of why they were suppressed so you can review it if needed, and so the same contact does not accidentally get re-added to a future list without the suppression being applied again.
Staying compliant
Suppression is also how we keep your campaigns compliant with email regulations including GDPR and CAN-SPAM.
Both require that opt-out requests are honoured promptly and permanently. Our suppression process ensures that any opt-out received is applied across all active and future campaigns immediately, not just the one it came from.
We do not provide legal advice, but we build the suppression process to align with the requirements of the markets you are operating in. If you are running campaigns across multiple geographies with different regulatory requirements we will discuss that with you during onboarding.
FAQ
What happens if a suppressed contact appears on a new list?
They get flagged and removed automatically. The suppression check runs on every list regardless of where it came from. A contact who opted out six months ago will never receive an email just because they ended up on a new list.
Can we add our own suppression criteria?
Yes. During onboarding we ask you to share any specific exclusions you want applied, such as competitor domains, partner organisations, or accounts being handled by your internal team. These get added to your custom suppression list and applied across all campaigns.
How quickly are opt-outs processed?
Immediately. When a reply comes in asking to be removed or when an unsubscribe link is clicked, that contact is added to the suppression list before the next send cycle runs. We do not batch process opt-outs on a delay.