What is SMS TPS? Throughput-Per-Second Explained
SMS TPS — transactions / messages per second — explained for Indian SMS workloads. How TPS is allocated, why it matters at sale-day, and how to size for OTP traffic.
StartMessaging Team
Engineering
SMS TPS — Transactions Per Second — is the rate at which a provider will accept your sends before throttling. For OTP-heavy apps with sale-day spikes, TPS is the number that decides whether your sale survives.
TPS — Definition
Maximum number of SMS submissions accepted by the gateway per second per account or sender ID.
Why TPS Matters
- Sale-day spikes can demand 50–200× normal TPS.
- Hitting TPS limit causes 429 throttling.
- Users see “OTP failed” at exactly the wrong moment.
TPS in Indian SMS
- Operators allocate TPS per sender ID.
- Defaults are conservative (10–30 TPS).
- Higher allocations require operator approval.
How to Size for OTP Traffic
- Average TPS = peak hourly OTPs / 3600.
- Plan for 5× the average for spike absorption.
- Test with sandbox load before launch day.
FAQ
StartMessaging auto-elastic TPS — no fixed cap as long as wallet is funded. Contact support before IPL-scale events for capacity planning.
Related Articles
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Design phone OTP flows for high traffic: idempotency, rate limits, fraud signals, fallbacks, and observability—aligned with TRAI DLT transactional SMS expectations for Indian login and payments.
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