Opt-in refers to the process of obtaining explicit consent from a consumer before sending them marketing text messages. Under TCPA, prior express written consent is required for all promotional SMS communications.
Types of Opt-In
Single Opt-In
Consumer provides phone number and agrees to receive texts
One-step process
Higher list growth, but lower quality
Double Opt-In (Recommended)
Consumer provides number and agrees
Confirmation text sent requiring reply (e.g., "Reply YES to confirm")
Lower list growth, but higher quality and legal protection
Valid Opt-In Methods
1. Web forms: Checkbox with clear disclosure
2. Text-to-join: Consumer texts keyword to short code
3. Paper forms: Physical signup with signature
4. Point-of-sale: Digital consent at checkout
5. In-app: Mobile app permission flow
Opt-In Requirements
Cannot be pre-checked
Must be separate from other consents
Must clearly state it's for SMS marketing
Must include frequency disclosure
Must note data rates may apply
Must provide opt-out instructions
Best Practices
Send immediate welcome message
Confirm what they're subscribing to
Deliver value quickly
Keep records with timestamps
Don't purchase phone lists