Blocklist
What is Blocklist?
A blocklist is the set of destinations or categories a sending platform permanently refuses to deliver to — phone numbers, email addresses, recipient domains, or abusive sending patterns. Entries that never move are enforced as a hard send-time gate: any outbound message aimed at a blocklisted destination is dropped before dispatch, so no campaign, import, or API call can reach it. A blocklist answers the opposite question of an allowlist: deny by default, not permit by default.
More detail
In messaging and email trust-and-safety usage a blocklist is enforced at send time, not remembered and filtered upstream: once a destination (or a category — a fraud pattern, a regulated industry outside your terms, a scam-prone content class) is on the list, every downstream send path drops it before dispatch. That is what distinguishes a blocklist from a ranking or scoring filter: entry on the list is binary, and the gate is absolute.
Orbit already treats this deny-side gate as policy: the suppression pipeline drops a suppressed destination from every outgoing campaign or API call at dispatch, and the tenant's own captured opt-outs aggregate into that deny list. The blocklist concept names the policy itself — the set a sender has resolved should never be reached, regardless of channel or campaign.
Frequently asked
- How does a blocklist differ from a suppression list?
- Both are deny lists enforced as hard send gates. A suppression list is the recipient-opt-out half — STOP replies and unsubscribes the sender captured. A blocklist is the broader trust-and-safety policy term: it also covers prohibited categories, known-fraud patterns, and destinations a sender resolved to never reach again — a recipient opt-out is one entry class among several.
- Is a blocklist the same thing as a DNC registry?
- No. The DNC registry is a public central list — recipients join once and every sender respects it. A blocklist is sender- or platform-owned. Both get enforced independently at send time; neither substitutes for the other.
- What is the opposite of a blocklist?
- An allowlist — the set of destinations explicitly approved to receive. Blocklists answer deny-by-default; allowlists answer permit-by-default. Both are enforced as hard gates at dispatch rather than filtered upstream.
See also
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