Keywords and auto-replies

Three keywords are required on every approved number. The platform processes them at the carrier layer before any message reaches your agent or workflow — so even if a campaign you build forgets to handle them, the legal floor is enforced for you.

The three required keywords

STOP — opt out

Recognized variants (case-insensitive): STOP, UNSUBSCRIBE, CANCEL, END, QUIT, OPTOUT, OPT OUT, STOPALL. Any of these triggers an immediate suppression for that number on that brand. Subsequent messages are blocked at the carrier level.

Default reply we send:

[Brand name]: You are unsubscribed and will receive no further messages.

HELP — get help

Recognized variants: HELP, INFO, SUPPORT. Returns information so the recipient can reach the brand.

Default reply we send:

[Brand name]: Please reach out to us at [website / email / phone] for help. Reply STOP to opt out.

START — opt back in

Recognized variants: START, UNSTOP, YES (after a previous STOP). Removes the suppression and allows messages again.

Default reply we send:

[Brand name]: You are re-subscribed. Reply HELP for help, STOP to opt out. Msg & data rates may apply. Message frequency may vary.

Opt-in confirmation

For marketing-style campaigns and any campaign with recurring messaging, the very first message a new opt-in receives should confirm enrollment. Carriers expect this confirmation to include all of the elements that go on the opt-in form itself:

[Brand name]: Thanks for subscribing to [use case]! Reply HELP for help. Message frequency may vary. Msg & data rates may apply. Consent is not a condition of purchase. Reply STOP to opt out.

Customizing the replies

The default replies above are sent automatically, but you can customize the body for each campaign — for instance, to include the brand's support hours or a link to a help center. Customizations must keep all the required elements: brand name, opt-out instruction (for HELP), and the no-promotional-content rule (auto-replies cannot include marketing).

What you must never do

• Ignore a STOP and keep messaging that number. Even one follow-up message after STOP is a carrier violation.
• Use a different number to "get around" a STOP. STOP is enforced per brand, across all numbers.
• Make HELP a sales pitch. The reply must be informational.
• Require a multi-step opt-out flow ("reply STOP, then click a link, then confirm"). One message — STOP — opts the recipient out, full stop.