Understanding Custom SMS Opt-In Keywords

Fans can opt in for SMS messaging by either filling out a form you’ve shared, or by texting an opt-in keyword to your Sonikit phone number. This article explains what opt-in keywords are and how they work.

What are Opt-in Keywords?

Opt-in keywords are short words or phrases that fans text to your number to subscribe to your messages. For example, if your phone number is +1 (555) 123-4567, a fan could text START to that number to join your SMS list.

When a fan sends an opt-in keyword:

  1. They’re automatically added to your fan list in Sonikit.

  2. Their consent to receive SMS messages is recorded.

  3. You can begin including them in your future SMS campaigns.

Default Opt-in Keywords

By default, your Sonikit messaging number supports Twilio’s standard keywords:

Action

Default Keywords

Opt-in

START, YES, UNSTOP

Opt-out

STOP, STOPALL, UNSUBSCRIBE, CANCEL, END, QUIT

Help message

HELP, INFO

These defaults are always active and recognized automatically — even if you create custom keywords.

Why Create Custom Keywords?

Custom keywords let you create a more branded experience for your fans.
For example:

  • A record label could use “JOINLABEL” or “VIPACCESS”.

  • An artist could use “SIGNUP” or “FANCLUB”.

You can use up to 5 custom keywords, each up to 10 characters long.

Availability

Custom opt-in keywords are available on:

  • Pro plan

  • Enterprise plan

If you’re on the Basic plan, you can still use the default keywords but won’t be able to add custom ones.

Next Steps

To set up your own custom opt-in keywords, see the next article:
➡️ How to Set Up Custom SMS Opt-in Keywords