# Consent and the 24-hour window

> Who may receive which message. Opt-in states, free text inside the 24-hour window and approved templates outside of it.

Last updated: 2026-10-30. Source: https://docs.smartchat.marketing/en/concepts/consent-and-24h-window/

WhatsApp has strict rules. The API enforces them on the server. You cannot send around them, even with a key that has every permission.

## Opt-in

Each contact has a field `optin_whatsapp`:

| Value | Meaning |
|---|---|
| `none` | No opt-in asked yet. |
| `pending` | An opt-in message was sent, no answer yet. |
| `confirmed` | The contact said yes. |
| `opted_out` | The contact unsubscribed. |

Which kind of message a contact may receive depends on this value:

| Kind of message | `none`, `pending` | `confirmed` | `opted_out` |
|---|---|---|---|
| Free text, inside the 24-hour window (send message call) | yes | yes | yes, only as an answer inside the open window (the person just wrote to you) |
| Free text, window closed | `window_closed` | `window_closed` | `contact_opted_out` |
| Approved template (send template message call) | `contact_not_confirmed` | yes | `contact_opted_out` |
| Newsletter | not sent, counted as `not_confirmed` | yes | not sent, counted as `opted_out` |
| Opt-in request (opt-in confirmation call) | only `none` without a running request; `pending` is skipped | skipped, not needed | never |
| Test send | yes, the number does not need to be a contact | yes | `contact_opted_out` |

A number on the suppression list gets nothing at all and the answer is [`number_suppressed`](https://docs.smartchat.marketing/en/errors/#number_suppressed).

- The API **never sets a contact to `confirmed`**. Only the contact can confirm, by answering the opt-in message. You can ask for the opt-in with the opt-in confirmation call.
- A newsletter only goes to contacts with `confirmed`.
- Only a contact with `confirmed` can be unsubscribed through the API. For any other contact the unsubscribe call answers [`contact_not_confirmed`](https://docs.smartchat.marketing/en/errors/#contact_not_confirmed), because such a contact gets no marketing anyway.
- A call that tries to send to a contact who may not receive it fails with [`contact_not_confirmed`](https://docs.smartchat.marketing/en/errors/#contact_not_confirmed), [`contact_opted_out`](https://docs.smartchat.marketing/en/errors/#contact_opted_out) or [`number_suppressed`](https://docs.smartchat.marketing/en/errors/#number_suppressed).

## The 24-hour window

After a contact writes to you, a window of 24 hours opens. Inside it you may send **free text**. After it closes, free text is not possible. The answer is [`window_closed`](https://docs.smartchat.marketing/en/errors/#window_closed). Send an approved template instead.

## Approved templates only

Outside the inbox, messages go out only as templates that WhatsApp has approved. Variables in a template are filled with values you send; missing values give [`template_variables_missing`](https://docs.smartchat.marketing/en/errors/#template_variables_missing). A template that is not approved gives [`template_not_approved`](https://docs.smartchat.marketing/en/errors/#template_not_approved).

This also holds for test sends: a test goes to the number you name, but only with an approved template, and never to a contact who unsubscribed.

## Unsubscribing

Use the unsubscribe call to mark a contact as `opted_out`. This cannot be undone through the API.