What is 10DLC?
10DLC stands for 10-Digit Long Code. It's a system that US mobile carriers (AT&T, T-Mobile, Verizon) implemented to regulate business-to-consumer text messaging. Think of it as a registration system that tells carriers: "This number is legitimate, and the messages it sends are wanted by the recipients."
Why Should You Care?
If you're sending SMS messages to event guests from an unregistered number, carriers will likely:
- Throttle your messages: Delivery slows to a crawl
- Filter your messages: Some guests never receive them
- Block your number entirely: Your event communication goes dark
This is why DIY SMS solutions (using a personal number or unregistered Twilio account) are risky for events with more than a handful of guests.
How MustardSMS Handles Compliance
Every MustardSMS number is registered under our verified 10DLC campaign. This means:
- High deliverability: Your messages reach guests reliably
- Action-based consent: When a guest clicks "Confirm RSVP," that's their consent. No awkward checkboxes.
- Automatic STOP handling: Guests can opt out anytime by replying STOP, and the system respects it immediately
- Anti-blast protection: Outbound messages are capped at 50 per minute to protect deliverability
The Consent Question
One of the most common compliance concerns is consent. How do you prove a guest agreed to receive messages? With MustardSMS, consent is action-based: the guest actively scans a QR code, fills in their information, and taps "Submit RSVP." This action serves as documented consent under current carrier requirements.
No hidden checkboxes. No pre-checked opt-ins. Just a clear, intentional action.
What Happens When an Event Ends?
Data hygiene matters. MustardSMS enforces strict data lifecycle policies. Phone numbers associated with completed events are released after a defined retention period. Guest data is siloed per-event and never shared across organizers.
Compliance isn't just about following rules. It's about building trust with your guests.