Twilio Incident Resolved: SMS Delivery Delays to Claro Colombia Network Restored
After a grueling 36-hour period that left Colombian businesses scrambling for backup communication channels, Twilio's SMS delivery to Claro Colombia's network has returned to normal operations. The incident, which affected potentially millions of users across Colombia's largest mobile network, serves as a stark reminder of how deeply modern business operations depend on seemingly simple text messaging infrastructure.
The Scale of Impact
The numbers paint a sobering picture. Claro Colombia holds approximately 40% of the mobile market share as of Q3 2025, making them the largest provider in Colombia, according to Statista (November 2025). With an estimated 38 million mobile subscribers in Colombia in 2025, Claro's 40% market share suggests approximately 15.2 million subscribers were potentially impacted by SMS delivery issues (calculated from Statista data, July & November 2025).
The SMS delivery delays to Claro Colombia lasted for approximately 36 hours, with approximately 25% of messages experiencing significant delays and 5% failing completely, per Twilio's Engineering Blog (January 2026). For businesses relying on time-sensitive communications—think banking verification codes, delivery notifications, and appointment reminders—these weren't just statistics. They represented lost sales, frustrated customers, and operational chaos.
An estimated 5,000 businesses in Colombia rely on Twilio's SMS infrastructure for critical communications, including banking OTPs, delivery notifications, and emergency alerts, based on Twilio internal data (December 2025) and an Asomóvil report (2025). Each of these businesses had to navigate a communications minefield during the outage window.
Technical Resolution and Root Cause
While Twilio hasn't released granular technical details about the root cause, carrier interconnection issues between international messaging providers and regional networks aren't uncommon in Latin American markets. These problems often stem from capacity constraints, routing table conflicts, or authentication handshake failures between different network protocols.
The resolution appears to have involved coordination between Twilio's engineering teams and Claro's network operations center. Given the 36-hour resolution timeline, we can reasonably assume this wasn't a simple configuration fix but required deeper investigation into the messaging pathway between both networks.
What's particularly noteworthy is how this incident contrasts with Twilio's typical reliability metrics. Twilio's reported global uptime for SMS delivery in 2025 was 99.95%, exceeding their current Service Level Agreement (SLA) commitment for SMS delivery of 99.9%, according to Twilio's Trust & Security Page (December 2025) and their SLA documentation (January 2026).
Business Continuity Lessons
This incident highlights critical vulnerabilities in single-provider SMS strategies. Colombian enterprises learned the hard way that even industry-leading providers can face regional carrier-specific failures. Smart businesses will take several lessons from this outage:
First, implement multi-channel fallback strategies. When SMS fails, having WhatsApp Business API, email, or push notifications ready to deploy can mean the difference between minor inconvenience and major revenue loss.
Second, consider geographic SMS redundancy. Some enterprises are now exploring dual-provider strategies, maintaining accounts with both international providers like Twilio and regional SMS aggregators who might have different routing paths to local carriers.
Third, monitor proactively. Companies that detected the issue early through automated monitoring could switch to backup channels faster than those waiting for customer complaints.
Moving Forward
Twilio's standard policy for regional SMS delivery incidents offers service credits to affected enterprise customers, typically calculated based on the percentage of impacted traffic and the duration of the outage, with credits usually applied to future invoices, per Twilio Support Documentation (January 2026). But for most businesses, credits don't compensate for lost customer trust or missed opportunities.
The Colombia incident underscores a broader challenge in Latin American telecommunications infrastructure. As businesses increasingly rely on cloud communications platforms, the resilience of regional carrier interconnections becomes a critical business risk that deserves board-level attention.
Conclusion
While service has been restored, the Twilio-Claro incident won't be quickly forgotten by Colombian businesses. It's forced a necessary conversation about communication redundancy, vendor dependency, and the hidden fragility of our hyper-connected business operations. Companies that treat this as a wake-up call rather than a one-off glitch will emerge more resilient and better prepared for the next inevitable hiccup in our global communications infrastructure.