Zvanta Blocklist is a hard customer blocklist that works inside checkout. Add an email, phone or delivery address and the order simply cannot be placed — including express checkouts, where banner apps never load. Smart matching catches Gmail aliases, phone prefixes and spelling tricks. Orders that slip through other channels are tagged instantly and can be auto-cancelled with a full refund. Buyers only ever see a neutral message. Your list is encrypted at rest; GDPR erasure is automatic.

• Hard checkout block by email, phone or address — works in express checkout too
• Smart matching: Gmail aliases, phone prefixes and typos cannot dodge the list
• Auto-cancel with refund for orders that slip through the checkout block
• One-click „block from order #” plus CSV import of existing lists
• Neutral decline message — buyers never learn they are listed (GDPR-safe)