Opt-in

Opt-in is the action by which a person gives explicit consent to receive commercial communications from a brand through a specific channel: email, WhatsApp, SMS or notifications. It is the legal and operational foundation of all permission marketing: without a valid, recorded opt-in, no promotional message should be sent, because that permission is what separates a legitimate communication from spam.

In practice, opt-in happens when someone fills out a form, checks a box, replies "Yes" to a message or subscribes to a newsletter, and that action is stored with date, time and source. Managing who gave permission (and for what) is part of what Revio automates, keeping contact lists in sync with each person's consent status.

The golden rule is simple: opt-in must be freely given, informed, specific and unambiguous. A pre-checked box or a permission "buried" in terms and conditions nobody reads does not count.

Why opt-in matters

Opt-in is not an annoying legal formality: it is the difference between building an audience that wants to hear from you and a list that marks you as spam. When a person gives permission consciously, they are much more likely to open, read and reply. That is why contact databases with genuine opt-in have better open and conversion rates than purchased or scraped lists, which tend to end up in the junk folder and drag the sender's reputation down.

On channels like WhatsApp, opt-in is no longer optional: it is a technical requirement. Meta requires the business to have recorded permission before sending the first template message; without that consent, bulk sends hurt your WhatsApp quality rating and can lead to the number being blocked. Something similar happens with email: mailbox providers (Gmail, Outlook) track spam complaints, and a database without opt-in triggers them.

How it works in practice

Consent is captured and stored at different touchpoints. The most common are:

• Landing page forms: the user leaves an email or phone number and agrees to receive communications by checking a box (never pre-checked).
• Newsletter signup checkbox: in a website footer or inside an e-commerce shopping cart.
• Click-to-WhatsApp or direct reply: when someone starts a conversation or replies "I want to receive updates", that action already counts as an opt-in.
• Physical touchpoints: a QR code in the store or a coupon offered in exchange for permission.

Every time an opt-in is recorded, it is worth storing the date, the source and the exact wording the person accepted. That record is the proof that backs you up in an audit or a complaint.

Single opt-in vs. double opt-in

There are two approaches, and choosing the wrong one is costly. Single opt-in adds the contact as soon as they submit the form; double opt-in adds a confirmation step: the person receives an email (or a message) and must click to confirm that the address is theirs and that the permission was real.

For a serious marketing database, double opt-in usually wins: it grows more slowly but leaves a clean list, with real addresses and consent that holds up to any legal review.

A concrete example in Argentina

Picture a retail chain building its loyalty program. At checkout, customers are offered a discount if they subscribe via WhatsApp. The customer scans a QR code, the chat opens and they reply "Yes, I want the discounts." That message is the opt-in. The system records it with date and source ("QR checkout, Córdoba store"), and only then can the brand send promotions through templates. If the chain had instead manually uploaded every phone number from its receipts without asking for permission, every send would be a violation and a direct risk of Meta shutting the number down.

Locally, Argentina's Personal Data Protection Law (Law 25,326) and its enforcement authority require consent to process data for commercial purposes, and recognize the person's right to withdraw it at any time (the opt-out). A well-executed opt-in is, in effect, your compliance insurance.

Common mistakes

• Pre-checked boxes: they invalidate consent; it must be an affirmative action by the person.
• Not keeping proof: without date, source and accepted wording, you cannot show you had permission.
• Reusing a list for another channel: an email opt-in does not automatically allow you to message someone on WhatsApp; permission is channel-specific.
• Ignoring opt-outs: if someone unsubscribes, you must honor it immediately; continuing to send destroys your reputation and exposes you to penalties.
• Confusing past contact with permission: the fact that someone bought from you does not mean they agreed to receive advertising.