# Manage SMS Consent and Opt-Outs

SMS consent and opt-out handling determine whether a recipient may receive promotional messages. Engage Studio records subscription events and Twilio blocks opted-out numbers, but you must maintain consent records and exclude opted-out profiles from future audiences.

## Manage Consent Outside Engage Studio

Obtain the consent required for your use case before sending a promotional SMS. Manage consent capture in the systems where customers provide permission, such as a web form or checkout flow, and retain the records in your CDP.

Engage Studio does not collect or retain consent records on your behalf. Before launching a campaign, apply the appropriate consent and opt-out filter in the Parent Segment or activation.

## Process STOP Keywords

Twilio Advanced Opt-Out processes these opt-out keywords:

```text
STOP, STOPALL, UNSUBSCRIBE, END, QUIT, CANCEL
```

When a recipient sends an opt-out keyword:

1. Twilio blocks future outbound messages to the number and sends an opt-out confirmation.
2. Engage Studio writes the event to `subscription_events`.
3. The profile remains in your CDP until you update the audience or profile data.


Use [View SMS Delivery Events](/products/marketing-cloud/engage-studio/channels/sms/view-sms-delivery-events) to find the recorded subscription event.

Important
Opt-out events are not automatically synchronized into your Parent Segment. Exclude the recipient before the next campaign.

## Process START Keywords

Re-opt-in requires the recipient to send a keyword. Supported opt-in keywords include:

```text
START, YES, UNSTOP
```

A re-opt-in cannot be triggered through an API or website. Do not re-enroll an opted-out recipient without their explicit keyword action.

## Compliance Responsibilities

The sending organization is responsible for obtaining consent, retaining consent records, honoring opt-outs, and following applicable regulations. See [SMS Message Requirements and Limits](/products/marketing-cloud/engage-studio/channels/sms/sms-message-requirements) and [Configure SMS Delivery Windows](/products/marketing-cloud/engage-studio/channels/sms/configure-sms-delivery-windows) for related requirements.

## Related Pages

- [Set Up SMS Sending](/products/marketing-cloud/engage-studio/channels/sms/set-up-sms-sending)
- [Create an SMS Campaign](/products/marketing-cloud/engage-studio/channels/sms/create-sms-campaign)
- [View SMS Delivery Events](/products/marketing-cloud/engage-studio/channels/sms/view-sms-delivery-events)