The one-sentence version#
Consent is the documented permission a recipient gives to receive marketing email. Laws differ on whether it must be express (opt-in) or may be implied (existing relationship), and on how long it lasts.
Why you should care#
Consent is the legal basis for marketing mail in most jurisdictions and the practical basis for good deliverability: people who asked for mail rarely complain.
The mental model#
Think of email consent management as a contract between you and the mailbox providers receiving your mail. You publish or configure something they can check; they check it on every message; the result feeds their decision about where your message lands. Everything below is about making that check pass consistently.
Your first setup, step by step#
- Use an unchecked checkbox or a dedicated signup form; never pre-tick.
- Record timestamp, IP, source, and the exact wording shown at consent.
- Use double opt-in for marketing lists where feasible.
- Separate consent for different purposes (newsletter vs partner offers).
- Refresh consent for contacts older than two years with no engagement.
Words you will see#
- Mailbox provider: Gmail, Microsoft, Yahoo, Apple, and the corporate gateways that decide where mail lands.
- Authentication: proof that a message is from who it says it is (SPF, DKIM, DMARC).
- Reputation: the provider's running score of your domain and IP.
- Placement: whether a message reaches the inbox, spam, or is rejected.
Common mistakes#
- Bundling marketing consent into terms of service acceptance.
- Losing consent records during a CRM migration.
Frequently asked questions#
Is double opt-in required by law?
Not explicitly in most jurisdictions, but it is the easiest way to prove consent under GDPR and CASL and it improves list quality.