Voice OTP
A spoken one-time passcode read aloud in the user's language. The standard fallback for failed SMS OTP, and the way to reach users who cannot receive SMS — landlines, roaming, and VoIP numbers.
Voice API · Voice OTP & IVR · since 2003
A Voice API for Voice OTP when SMS can't get through.
Deliver spoken one-time passcodes, verify users with a flash call, route callers through multilingual IVR, and place programmable outbound calls for alerts and reminders — all on the same operator-direct network that carries BroadNet's SMS. Text-to-speech in Arabic and 30+ languages.
ISO 27001 30+ TTS languages 200+ countries
BroadNet · programmable voice
Voice network
30+
TTS languages
200+
countries
99.99%
SLA
What is BroadNet Voice?
BroadNet Voice is a programmable voice platform for authentication and engagement. It speaks one-time passcodes aloud as a fallback when SMS OTP fails, verifies users with a flash call, runs interactive voice-response menus and surveys, and places automated outbound calls for alerts and reminders. Every call rides the same operator-direct network as BroadNet's SMS — 1,000+ operator connections across 200+ countries — with text-to-speech in Arabic and 30+ languages.
Reach
200+
countries reached
Voice on the same global footprint as SMS.
Network
1,000+
operator connections
Direct interconnects, not aggregator hops.
Voices
30+
TTS languages
Including Arabic MSA and Gulf dialects.
Heritage
2003
operating since
Carrier-grade voice and messaging heritage.
What you can build
Four voice primitives, one REST API.
The same endpoint that sends your SMS places calls, reads codes, runs menus and triggers reminders — no separate voice stack to integrate or operate.
Flash-call verification
Verify possession of a SIM with a short missed call the user never has to answer. Faster and cheaper than a code where regulation allows. See flash-call.
IVR & surveys
DTMF-driven menus, self-service flows, surveys, queue routing and voicemail drops. Script prompts per language so one flow serves a multilingual audience.
Programmable voice
Automated outbound calls for alerts, reminders and notifications — payment-due nudges, delivery ETAs, appointment confirmations and critical service notices, with text-to-speech and keypad capture.
Capabilities
What's in the platform.
| Capability | What it does | Typical use |
|---|---|---|
| Voice OTP (TTS) | Reads a one-time passcode aloud, digit-by-digit, in the user's language | SMS OTP fallback, high-trust login |
| Flash-call verify | Short missed call the user need not answer; verifies SIM possession | Low-friction sign-up verification |
| IVR menus | DTMF prompt-and-response flows, surveys, queue routing, voicemail drops | Self-service, confirmations, feedback |
| Programmable outbound | API-triggered automated calls with a script or TTS message | Alerts, reminders, notifications |
| Text-to-speech | Natural speech in 30+ languages incl. Arabic MSA and Gulf dialects | Localised codes and prompts |
| Local DIDs | Local caller-ID numbers provisioned in 60+ countries | Higher answer rates, local presence |
| SMS → voice failover | Auto-escalate to a voice call when an SMS DLR does not return in time | Resilient OTP delivery |
| Delivery events | Per-call outcome and keypad responses pushed to your webhook | Auditing and analytics |
How it routes
One request, two channels — the phone rings when the text can't.
Voice OTP rides the same operator-direct network as BroadNet's SMS. A single request renders the code to speech, sends it by text first, watches for the delivery receipt, and escalates to a spoken call the moment SMS stalls — no second integration.
- 01 · RequestYour application
One REST call requests an OTP. Keep the returned ID so a retry never sends twice.
1 request - 02 · EdgeBroadNet edge
Auth, language pick, and text-to-speech render — the passcode becomes speech in the user's own tongue.
30+ langs - 03 · RouterChannel router
SMS goes first on a speed-tuned route; if no delivery receipt returns in time, the same code escalates to a voice call.
SMS → voice - 04 · OperatorOperator-direct
A direct interconnect to the destination carrier places the call from a local DID — no aggregator hops.
1,000+ direct - 05 · HandsetCode spoken
The passcode is read aloud digit-by-digit and repeated; the outcome is pushed to your webhook.
read ×2 - ← DLR timeout · escalate to Voice OTP
01 · Request
Your application
One REST call requests an OTP. Keep the returned ID so a retry never sends twice.
1 request
02 · Edge
BroadNet edge
Auth, language pick, and text-to-speech render — the passcode becomes speech in the user's own tongue.
30+ langs
03 · Router
Channel router
SMS goes first on a speed-tuned route; if no delivery receipt returns in time, the same code escalates to a voice call.
SMS → voice
04 · Operator
Operator-direct
A direct interconnect to the destination carrier places the call from a local DID — no aggregator hops.
1,000+ direct
05 · Handset
Code spoken
The passcode is read aloud digit-by-digit and repeated; the outcome is pushed to your webhook.
read ×2
Voice OTP as an SMS fallback
When the text stalls, the phone rings.
Set one timeout on your SMS OTP send. If the delivery receipt doesn't land in time, the platform reads the same code aloud as a Voice OTP call — no re-integration, and a channel field on the callback tells you which leg landed.
one request · two channels
01
Send OTP
Your app requests an OTP. The platform sends it over SMS on a speed-tuned direct route.
02
Watch the DLR
A timeout window (default 10s) waits for the SMS delivery receipt to return.
03
Escalate to voice
No receipt in time? The same code is placed as a Voice OTP call that reads it aloud.
04
Verify
User enters the code; the callback reports which channel delivered it, then context is purged.
The same failover ships inside BroadNet OTP — voice is the escalation leg its authentication flow calls automatically.
Use cases
Where teams reach for voice.
Fintech & banking 2FA fallback
When a login or high-value transfer OTP doesn't arrive by SMS, a Voice OTP call reads the code so the customer is never locked out of their money. Critical for account recovery and step-up authentication.
Delivery & logistics alerts
Programmable outbound calls confirm a delivery window, announce a driver's arrival, or prompt a failed-delivery reschedule with a keypad response — reaching recipients who miss the notification.
Appointment reminders
Automated reminder calls for clinics, services and bookings, with an IVR option to press 1 to confirm or 2 to reschedule — cutting no-shows without staff on the phones.
Coverage & languages
Global reach, local voices.
Voice rides the same operator-direct network as BroadNet's messaging — 1,000+ operator connections across 200+ countries, built since 2003. Local DIDs in 60+ countries mean the number your users see is local, not international, which lifts answer rates. Text-to-speech speaks codes and prompts naturally in the caller's language.
Arabic (MSA)Arabic (Gulf)EnglishFrenchSpanishGermanItalianPortugueseRussianHindiUrdu+ 20 more
200+ countries
Every dialable destination BroadNet's SMS reaches, voice reaches too.
1,000+ connections
Operator-direct interconnects rather than aggregator hops.
Local DIDs · 60+ countries
Present a local caller ID so recipients recognise and answer.
Digit-by-digit codes
Passcodes spoken clearly and repeated for reliable capture.
Security & compliance
Audited for money and identity workloads.
Voice runs on the same certified infrastructure as BroadNet's messaging. Spoken codes and call context are purged on completion; every call leaves an auditable event trail.
ISO 27001
Information security management
ISO 27018
Personal data protection in public clouds
ISO 9001
Quality management system
ISO 22301
Business continuity
SOC 2 Type II
Report available under NDA
GDPR
Data Processing Agreement
How it fits
One layer of a multichannel stack.
Voice is rarely used alone. It's the escalation leg behind OTP, one channel in an omnichannel waterfall, and a companion to A2P SMS — all on the same network and the same API.
OTP delivery
Speed-tuned one-time passcodes with voice as the automatic SMS fallback.
Explore
Flash-call detection
The operator side of missed-call verification — detect, monetise or block.
Explore
Omnichannel
Rule-based waterfall across SMS, WhatsApp, RCS, Voice and Email.
Explore
A2P SMS
The messaging pillar voice complements — 300M+ messages a day, direct routes.
Explore
Developer API
The REST API for SMS and OTP, an official TypeScript SDK and an OpenAPI 3.1 spec. Voice and IVR are provisioned through your account team.
Explore
Best voice API provider
A buyer's guide comparing voice and Voice OTP vendors head-to-head.
Explore
FAQ
Voice, answered directly.
What is Voice OTP?+
Voice OTP delivers a one-time passcode as a spoken phone call instead of an SMS. Text-to-speech reads the code aloud — usually twice — in the recipient's language. It is the standard fallback when an SMS OTP does not arrive, and it reaches users who cannot receive SMS: landlines, roaming handsets, VoIP numbers, or destinations where the SMS route is temporarily degraded.
How does flash-call verification work?+
The platform places a very short call to the user's number from a code embedded in the caller ID or simply as a missed call. Your app reads the last digits of the calling number (or confirms the ring) to verify possession of the SIM — no code is typed, and often no call is even answered. It is cheaper and faster than SMS or spoken OTP where regulation permits it. See our operator-side flash-call detection for how carriers monetise and secure this traffic.
Which languages does text-to-speech support?+
BroadNet's text-to-speech covers 30+ languages, including Modern Standard Arabic and Gulf dialects, English, French, Spanish, German, Italian, Portuguese, Russian, Hindi, Urdu and more. Codes are spoken digit-by-digit for clarity, and IVR prompts can be scripted per language so the same flow serves a multilingual audience.
Can voice be used as an automatic fallback for SMS?+
Yes. Configure a timeout window on your SMS OTP send; if no delivery receipt returns in time, the platform escalates to a Voice OTP call that reads the same code. No re-integration is required — it is the same request, and a channel field on the callback tells you which leg succeeded. This is the SMS → voice failover pattern most fintech and banking flows run by default.
What is IVR and what can I build with it?+
IVR (interactive voice response) is a menu-driven voice flow: the caller hears prompts and responds with keypad tones (DTMF) or, on inbound calls, their voice. Use it for phone menus, self-service balance checks, appointment confirmation, surveys, queue routing, and voicemail drops. You build it with the same REST API you use for SMS and voice calls.
What can programmable outbound voice do?+
Programmable outbound voice places automated calls for alerts, reminders and notifications — payment-due reminders, delivery ETAs, appointment confirmations, fraud alerts and critical service notices. You supply the script or a text-to-speech message; the platform dials, plays it, captures any keypad response, and reports the outcome to your webhook.
Which countries and numbers does BroadNet Voice reach?+
Voice rides the same operator-direct network behind BroadNet's messaging — 1,000+ operator connections across 200+ countries, built since 2003. Local DIDs (caller-ID numbers) can be provisioned in 60+ countries so the number shown to your users is local rather than international, which lifts answer rates.
How is BroadNet Voice secured and certified?+
Voice runs on infrastructure certified to ISO 27001, ISO 27018, ISO 9001 and ISO 22301, with a SOC 2 Type II report available under NDA and GDPR compliance. Traffic is encrypted in transit, spoken codes and call context are purged on completion, and every call produces an auditable event record for your compliance team.
Carrier-grade delivery
Delivered to 200+ countries, direct to the operator in 86.
No grey routes: a direct operator bind wherever one is commercially available, otherwise a labelled partner-managed route. One API to every channel, on a network built since 2003.
200+
Countries
1,000+
Operator connections
300M+
Msgs·day
Voice infrastructure
Add voice to your verification flow.
Voice OTP as an SMS fallback, flash-call verification, IVR and programmable calls — on the operator-direct network trusted since 2003. Talk to our team about volumes, country mix and languages.
# Voice OTP · flash-call · IVR — one REST API, one integration
Resources
Voice datasheet
Related guides & answers
Go deeper on the concepts behind this product.