Glossary
What is opt-in consent?
Opt-in is a user's explicit, affirmative consent to receive communications or to have their data collected — required before the activity begins, rather than assumed until refused.
Opt-in and opt-out
The difference is the default, and it determines outcomes far more than most organisations expect.
Opt-out assumes consent and provides a way to withdraw it. Participation is high because inertia works in the collector's favour.
Opt-in assumes refusal and requires an affirmative act. Participation is far lower and the resulting population is genuinely willing.
LAT and ATT are the same choice under the two models, and the difference in participation between them was enormous.
What makes consent valid
- Freely given. Not a condition of access to something unrelated.
- Specific. To a stated purpose, not a blanket permission.
- Informed. In language the user actually understands.
- Unambiguous. A positive action — pre-ticked boxes do not qualify.
- Withdrawable, as easily as it was given.
Designing for it
The practical lesson from ATT is that timing and framing move opt-in rates more than anything else. A permission requested before the user understands the product is usually declined; the same request at a moment where the benefit is obvious performs several times better.
The other lesson is that a high opt-in rate obtained through a misleading prompt is a liability rather than an asset. Consent that would not survive being described plainly to the user is not consent, and regulators have been increasingly willing to say so.
Common questions
Does opt-in apply to contextual advertising?
Generally not, because contextual advertising uses no personal data — it matches an ad to what the user is currently doing. This is a large part of why contextual and conversational targeting have become more attractive.
Can I ask again after a user declines?
Platform rules limit re-prompting, and repeated asking is a poor experience regardless. The productive lever is asking better the first time, at a better moment.
Where we write about opt-in
More in privacy and compliance
The identifiers, consent signals and rules that bound targeting.