What type of consent is required under CASL (implied vs. express)?

Express consent is explicit permission obtained through a clear opt-in action. The urecipient affirmatively agreed to receive commercial messages. No pre-checked boxes allowed; the subscriber must take positive action. Express consent doesn't expire (until withdrawn) and provides the strongest legal protection. This is the gold standard for CASL compliance.

Implied consent is permission inferred from an existing relationship without explicit opt-in. It exists in two forms: existing business relationship (purchase, contract, membership within the past 2 years) grants 24-month implied consent; existing non-business relationship (donations, volunteer work, membership in organizations) also grants 24-month consent. Inquiries (requesting information, quotes) grant only 6-month implied consent.

The critical difference: implied consent expires. If you don't convert implied consent to express consent before the window closes, you must stop emailing that contact. CASL's structure incentivizes converting transaction-based contacts into explicit subscribers. Relying solely on implied consent creates operational complexity and legal risk-aggressive conversion to express consent simplifies compliance and improves list quality.