Prior consent is required, and the law explicitly states that consent does not transfer when a list is sold. 2. Choose a Reputable Data Provider

You do not need prior consent to send commercial emails, but you must include a clear opt-out mechanism, your physical postal address, and accurate sender information.

Buying email addresses for marketing is a controversial tactic that is but restricted or effectively illegal in the European Union (GDPR) and Canada (CASL) . While it offers a shortcut to reaching new audiences, most experts advise against it because it often leads to high spam complaint rates, damaged domain reputation, and account suspension from major email service providers (ESPs).

If you choose to proceed with buying a list, follow these best practices to mitigate risk: 1. Evaluate Legal Compliance by Region

Look for providers like BookYourData or Cognism that offer accuracy guarantees (often 95%+) and regular database updates.

Request a small sample of the list to test deliverability and relevance before committing to a full purchase. 3. Clean and Verify the List Before Sending

Ask the vendor how they collected the data and whether they have records of opt-in consent.