Twilio SMS Limits Disrupt Communication for 8,000 San Francisco Scavenger Hunt Participants

San Francisco, CA – An urgent plea from scavenger hunt organizer Riley Walz has highlighted the critical challenges of mass communication for large-scale events, as 8,000 participants were left untraceable due to Twilio SMS messaging limits. Walz took to social media, stating, > "anyone i know at twilio? kinda urgent, 8000 people signed up for a scavenger hunt in SF and we can't text them back because we hit limits..." The incident underscores the complexities of high-volume messaging platforms and their impact on time-sensitive operations.

Twilio, a leading cloud communications platform, implements various limits to ensure network stability and comply with carrier regulations. These typically include rate limits, measured in messages per second (MPS), and daily volume caps, particularly for Application-to-Person (A2P) messaging. While standard 10-digit long codes (10DLC) in the U.S. may have low default MPS, specialized sender types like toll-free numbers and short codes offer significantly higher throughput, crucial for events with thousands of participants.

For large-scale communications, Twilio recommends utilizing "Messaging Services" to manage sender pools and optimize delivery. Organizations are advised to select appropriate sender types, such as short codes (offering 100+ MPS) or verified toll-free numbers, which can be configured for higher message volumes. The practice of "snowshoeing," or using multiple long codes to bypass throughput limits, is generally discouraged and can lead to messages being filtered or blocked by carriers.

The U.S. messaging landscape is further shaped by A2P 10DLC regulations, which require businesses to register their messaging campaigns. This registration process influences assigned trust scores, directly impacting daily message caps imposed by mobile carriers, which can range from a few thousand to hundreds of thousands of messages per day. Hitting these limits can result in severe delays or complete failure of message delivery, disrupting critical event logistics.

This incident serves as a stark reminder for event organizers and businesses relying on SMS for mass communication. Proactive planning, understanding platform-specific limits, and adhering to regulatory requirements are essential to ensure seamless and reliable engagement with large audiences. Utilizing Twilio's specialized services and optimizing messaging strategies can prevent communication breakdowns in high-stakes scenarios.