SMS Opt-In and Opt-Out: How Consent Works in JustCall

Stay compliant4 min readUpdated 2026-03-12

SMS Opt-In and Opt-Out: How Consent Works in JustCall

US carriers and the TCPA require documented consent before you send business text messages. JustCall enforces opt-out processing automatically, but you are responsible for collecting opt-in consent before sending the first message.

Available on: All plans


Opt-In: Getting Permission to Text

Before texting a customer, you need their consent. The type of consent depends on what you're sending.

Message typeRequired consentExample
Transactional (order confirmations, appointment reminders, delivery updates)Express consentCustomer provides their phone number at checkout
Promotional (offers, marketing campaigns, product announcements)Express written consentCustomer checks a checkbox agreeing to receive marketing texts
Conversational (reply to a customer who texted you first)Implied consentCustomer initiates a text conversation with your number

What counts as valid opt-in

  • A web form where the customer enters their phone number and checks a consent box
  • A verbal agreement during a phone call (document it in your CRM)
  • The customer texts your number first (opt-in for that conversation thread)
  • A paper form with a signature (e.g., at a retail location or trade show)

What does NOT count as valid opt-in

  • Purchasing a contact list
  • A customer giving you their number for calling purposes only
  • Pre-checked consent boxes on web forms
  • Scraping numbers from websites or social media

Opt-Out: Automatic Processing

JustCall handles opt-outs automatically. When a recipient sends any of these keywords, the system processes it instantly:

Opt-out keywords: STOP, UNSUBSCRIBE, CANCEL, END, QUIT

What happens:

  1. JustCall sends a confirmation: "You have been unsubscribed. Reply START to resubscribe."
  2. The contact is marked as opted out in JustCall.
  3. All future outbound SMS to that number is blocked — across your entire account, not just one number.

You cannot:

  • Override an opt-out manually
  • Remove the opt-out flag without the customer re-subscribing
  • Send "one more message" after an opt-out

This is enforced at the carrier level. Attempting to bypass opt-outs will result in carrier filtering and potential number suspension.


Re-Subscribe: Opting Back In

A previously opted-out contact can re-subscribe by texting:

Re-subscribe keywords: START, UNSTOP, YES

JustCall automatically:

  1. Removes the opt-out flag.
  2. Sends a confirmation: "You have been resubscribed to messages from [Your Business]. Reply STOP to unsubscribe."
  3. Re-enables messaging to that contact.

Managing Opt-Out Status

View opted-out contacts

Go to Settings → SMS Settings → Opt-Out List to see all contacts who have opted out. This list shows:

  • Phone number
  • Date of opt-out
  • The JustCall number they opted out from

Bulk opt-out (suppression list)

If you have a list of numbers that should not receive messages (e.g., from a previous DNC request), you can upload them as a suppression list:

  1. Go to Settings → SMS Settings → Opt-Out List.
  2. Click Import.
  3. Upload a CSV with phone numbers in E.164 format (+1XXXXXXXXXX).

Required Disclosures in Your First Message

When texting a customer for the first time, include:

  1. Your business name — so they know who's texting.
  2. What they'll receive — the type of messages (e.g., "appointment reminders").
  3. How to opt out — "Reply STOP to unsubscribe."
  4. Message frequency — how often you'll text (e.g., "up to 4 msgs/month").
  5. Rates notice — "Msg & data rates may apply."

Example first message:

Hi Sarah, this is Dr. Smith's office. We'll send appointment reminders and follow-ups to this number. Reply STOP to opt out. Msg & data rates may apply.


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