Voice
Reach every user, even when SMS can't
Automated voice calls for OTP delivery, fraud alerts, and critical notifications — with intelligent retry from SMS workflows.
Why Katembe Voice
Built for reliability when it matters most
Global coverage
Place calls across 190+ countries with local carrier integrations optimized for connection rates.
Intelligent fallback
Automatically escalate from SMS to voice when delivery fails or times out.
Text-to-speech
Deliver dynamic OTP codes and custom messages via natural-sounding TTS voices.
High reliability
SLA-backed call delivery with real-time status events for every attempt.
OTP Delivery
Spoken verification codes that reach every user
When SMS OTP fails — due to carrier filtering, low signal, or feature phone limitations — voice delivery ensures your verification flow completes. Katembe selects the optimal TTS voice and pacing for each region.
Learn more about OTP verificationCritical Alerts
Escalate fraud and security events instantly
For high-stakes notifications — fraud alerts, account lockouts, payment failures — voice calls cut through when push and SMS are ignored. Configure escalation chains that trigger automatically from your messaging workflows.
Explore alert workflowsSimple integration
One API call to place a voice call
Integrate voice delivery in minutes. The same API key and client library used for SMS and WhatsApp — no separate vendor contracts or SIP configuration required.
curl -X POST https://api.katembe.io/v1/voice/calls \
-H "Authorization: Bearer <api_key>" \
-d "to=+258840000000" \
-d "template=otp_voice" \
-d "locale=pt-MZ"
"Katembe Voice cut our OTP drop-off rate by 18% in rural markets where SMS coverage is unreliable. It just works."
Pricing
Pay only for connected calls
Simple per-call pricing with no setup fees. Volume discounts available for enterprise accounts.