OTP SMS API for login verification, transaction authentication and account security. Integrate through API with DLT-compliant messaging support and real-time delivery reporting.
Quick answer: OTP SMS verification sends a short, auto-expiring numeric code to a user's mobile number to confirm identity during login, signup, or a transaction. MetaReach provides OTP SMS and delivery reporting, supports TRAI/DLT compliance requirements, and uses the DLT configuration and content-template category applicable to the sender/entity type, communication purpose, and current TSP/DLT requirements.
As an OTP service provider in India, we route OTP SMS using the DLT configuration and content-template category applicable to the sender/entity type, communication purpose, and current TSP/DLT requirements, with voice OTP fallback available when SMS can't get through.
Every time a user logs in, makes a payment, or activates an account on your platform, they're waiting for that one SMS. Delivery delays can lead to retries or abandoned flows. That's the problem we help businesses address.
MetaReach provides OTP SMS gateway and API services with delivery reporting. We can assist with applicable DLT onboarding, sender-header and content-template requirements.
From startup apps running a few hundred OTPs a day to enterprise platforms sending millions a month, our infrastructure scales with you. Beyond OTP, our platform also powers Bulk SMS Services, Transactional SMS Service, WhatsApp Business API, and RCS Messaging all from a single account.
OTP SMS kya hai? Simply put, OTP SMS ek auto-generated one-time code hota hai jo user ke mobile number par unki identity verify karne ke liye bheja jata hai login, payment, ya signup ke waqt.
OTP SMS is an auto-generated one-time code sent to a user's mobile to verify their identity. It expires after a single use — far more secure than static passwords for login verification, transaction approval, and account security.
OTP SMS supports 2FA, user verification, and payment flows across banking, fintech, e-commerce, and healthcare in India. MetaReach provides OTP SMS messaging and delivery reporting, with support for applicable sender-header and content-template requirements. The applicable template/message category depends on the sender, entity type and OTP use case.
A randomly generated code that expires after a single use or a fixed time window. Cannot be reused making it fundamentally more secure than static passwords for any login verification flow.
Two-Factor Authentication (2FA) combines something the user knows (password) with something they own (their phone). 2FA SMS API is the most widely adopted second factor across Indian banking and fintech.
The user requests an OTP by SMS, enters the code on-screen, and the system confirms identity. Delivery time depends on operator/network conditions, routing, DLT configuration and destination availability.
Secure OTP delivery ensures login attempts and payment approvals are authorised by the actual account holder blocking unauthorised access and significantly reducing fraud exposure for businesses.
This is how an OTP SMS authentication flow works through MetaReach's secure OTP delivery infrastructure, powering banking OTP SMS, fintech OTP API, and e-commerce verification across India.
The user enters their registered mobile number on your login, payment, or registration screen to trigger the OTP SMS verification.
Your backend generates a cryptographically random one-time password typically 6 digits valid for a configurable expiry window.
Your system calls the MetaReach OTP SMS API (REST or SMPP) with the mobile number, applicable DLT-registered sender header and registered content-template configuration. The API returns a message ID right away for tracking.
MetaReach submits the mobile verification SMS using the applicable sender-header and content-template configuration. Delivery time depends on operator/network conditions, routing, DLT configuration and destination availability.
The user enters the OTP. Your system validates it authentication is complete. A delivery webhook confirms secure OTP delivery in real time.
An OTP sender is the infrastructure layer that generates, routes, and delivers one-time passwords to users' phones. Delivery delays can lead to repeated requests, failed authentication attempts, or abandoned flows.
MetaReach provides OTP SMS messaging and delivery reporting for fintech companies, e-commerce platforms, healthcare apps, and banking portals across India. Delivery time depends on operator/network conditions, routing, DLT configuration, destination availability and other telecom factors.
Compatible with popular verification workflows (including setups similar to Twilio Verify), so switching over is simple.
Per-message delivery report
Compliant sender & templates
Per OTP SMS
Technical support, 10:00 AM – 6:00 PM IST
An OTP API is the programmatic interface your backend calls to generate, send, and track one-time passwords no manual dashboard steps, no queues. Send a single request with the user's mobile number and a DLT-approved template; MetaReach's gateway handles routing and delivery, and returns a real-time response your application can act on immediately.
Every OTP sent through the API is routed using the DLT configuration and content-template category applicable to the sender/entity type, communication purpose, and current TSP/DLT requirements. This is not a blanket default classification: the applicable sender and template setup must match the actual use case and relevant DLT/TSP rules.
One GET request per OTP: API key, mobile number, sender ID and message (optionally your DLT template ID). No SDK required.
Every send returns a message ID; query the Delivery Report API with it to see submitted, delivered or failed status per number.
API requests can include the registered template and entity identifiers. These records must match the applicable DLT configuration and content-template requirements for the sender, communication purpose and use case.
Businesses can design multi-channel authentication workflows according to their approved WhatsApp setup, SMS configuration and application logic.
Our OTP API India is a standard REST endpoint. Integration time depends on the application's backend, authentication flow and implementation requirements. MetaReach provides API documentation and implementation support to help developers complete the integration efficiently. When a user needs verification SMS, your backend calls the endpoint with their mobile number and applicable DLT-registered sender header and registered content-template configuration to submit the OTP message. Delivery time depends on operator/network conditions, routing, DLT configuration and destination availability. Enterprise teams can connect via SMPP API for higher throughput. See our complete OTP API guide for request/response samples, SDKs, and REST vs SMPP comparison.
High-volume platforms (10 lakh+ OTPs/month) benefit from direct SMPP API connectivity. Lower latency, persistent connections, and throughput suited to banking OTP SMS and fintech OTP API workloads that REST alone can't serve at scale.
GET https://sms.metareach.in/vb/apikey.php ?apikey=YOUR_API_KEY &senderid=YOURID &number=91XXXXXXXXXX &message=Your%20OTP%20is%20482913 &templateid=170717XXXXXXXXXXX Response: { "status": "Success", "code": "011", "description": "Message submitted successfully", "data": { "messageid": "MzQz", "totnumber": "1" } } // track with the DLR API using messageid
Download ready-made script samples in PHP, Python, and Node.js. SMPP available for very high volumes.
SDK & Language Support
Pre-built SDK wrappers and code samples integrate OTP API India into your stack in minutes.
From fraud prevention and instant authentication to customer trust and secure login here's what actually matters when choosing a mobile verification service, and what sets MetaReach apart from generic SMS aggregators.
OTP SMS fraud prevention ensures only the account holder can approve a login or transaction. This secure login layer blocks most account takeover attempts especially critical for banking OTP SMS, fintech authentication, and healthcare platforms handling sensitive data.
Per-message delivery reports help teams review the status of transaction approval messages. Delivery time depends on operator/network conditions, routing, DLT configuration and destination availability.
SMS reaches every mobile in India feature phones, 2G connections, every operator. Unlike app-based authenticators, SMS OTP works for virtually every mobile user without any additional setup on their end.
Our SMS pricing is straightforward no monthly fees, no hidden charges, no confusing credit structures. Pay for what you send, with volume discounts as you scale.
India has over 900 million mobile users across every type of device and network. We route OTPs on SMS delivery across major operators, with delivery reports so you can see what reached each user.
Adding OTP verification to every transaction or login makes unauthorized access exponentially harder. For e-commerce and banking clients, this alone often justifies the cost fraud losses consistently outweigh SMS costs.
Commercial SMS in India is subject to applicable DLT requirements. MetaReach can assist with DLT onboarding, including Principal Entity registration guidance, sender-header registration and content-template registration. Processing and approval timelines depend on document completeness and the relevant DLT/TSP platform; any applicable service charges are communicated before processing.
Reliable account security through OTP supports customer trust. Clear delivery status and a well-designed verification flow help teams investigate delays and reduce friction for users.
Integration time depends on the application's backend, authentication flow and implementation requirements. MetaReach provides API documentation and implementation support to help developers complete the integration efficiently. Code examples are available in PHP, Python, Node.js, Java, and .NET. View the full API docs ?
Whether you're sending 500 OTPs a day or need SMPP connectivity for enterprise volumes, the same platform handles it. No migration as you grow just upgrade your plan or contact our team for a custom arrangement. Need more channels? Explore WhatsApp Business API and RCS Messaging for richer customer communication.
Networks occasionally drop a message. A well-designed retry mechanism stops that from becoming a failed login or an abandoned checkout without opening the door to OTP-spam abuse.
A short 30 60 second wait before a resend is allowed, preventing accidental double-sends and network flooding.
Typically 3 5 resend attempts per session, configurable to match your risk tolerance and user flow.
Limits per mobile number and per IP block scripted OTP-bombing attempts before they reach your users.
Voice OTP can be configured as an additional authentication channel or fallback option where appropriate, subject to the application's workflow and applicable telecom requirements. See our SMS to Voice OTP guide for setup information.
Voice OTP can be configured as an additional authentication channel or fallback option where appropriate, subject to the application's workflow and applicable telecom requirements.
Voice OTP can be configured as an additional authentication channel or fallback option where appropriate, subject to the application's workflow and applicable telecom requirements. See our SMS to Voice OTP guide for setup information.
An OTP is only as secure as the system generating, transmitting, and expiring it. These are the safeguards built into every OTP MetaReach delivers.
Codes typically expire within a few minutes, shrinking the window an intercepted OTP could ever be used in.
Each code is invalidated the instant it's verified or it expires whichever comes first.
API calls run over HTTPS/TLS end to end, so OTP payloads are never exposed in plain text on the wire.
The same retry limits and rate controls that manage resends also block scripted OTP-bombing and enumeration attacks.
We recommend pairing OTP with device or session signals for high-value actions, reducing exposure to SIM-swap fraud.
Codes are generated using a secure random source never sequential, never predictable.
TRAI's DLT (Distributed Ledger Technology) framework applies to commercial SMS in India, including OTP SMS. Businesses should complete the applicable Principal Entity, sender-header and content-template requirements. The applicable content-template category depends on the sender/entity type, communication purpose, use case and current TSP/DLT requirements. Messages that do not meet applicable registration and matching requirements may be rejected or blocked by the relevant TSP.
MetaReach can assist with the applicable DLT onboarding process, including Principal Entity registration guidance, sender-header registration and content-template registration. Processing and approval timelines depend on document completeness and the relevant DLT/TSP platform. Any applicable onboarding or service charges are communicated before processing.
Passwords alone don't prove who's on the other end of a login attempt they can be guessed, leaked, or stolen. OTP-based authentication adds a second, time-bound proof of identity tied to a device only the real user holds.
2FA (Two-Factor Authentication) combines something the user knows (a password) with something they hold (their registered phone). After a correct password, MetaReach sends an OTP to that phone; the login or transaction completes only once the code is entered correctly.
It's the most widely adopted second factor across Indian banking, fintech, and payments because it needs no app installation and works on every handset feature phones included.
Wiring 2FA into a login or checkout flow is a small addition on top of the same OTP API see our OTP API service guide for the integration steps. For sector-specific 2FA patterns, see OTP authentication for fintech apps and OTP authentication API for SaaS platforms.
Even a stolen or guessed password is useless without physical access to the registered device.
Automated login attempts using leaked password lists fail at the OTP step every time.
SMS-based 2FA can be used on compatible mobile devices without installing an authenticator app. Access depends on mobile service and destination availability.
Meets the additional-factor expectations common in banking, fintech, and payment workflows in India.
From banking OTP SMS and fintech OTP API to e-commerce OTP SMS and healthcare verification our OTP SMS platform supports authentication workflows where reliable verification matters.
Payment authorization, fund transfer verification, account login alerts, and EMI reminders all should follow the recipient-preference, consent and communication-category requirements applicable to the sender, use case and current TRAI/TSP framework. OTP SMS should follow the recipient-preference, consent and communication-category requirements applicable to the sender, use case and current TRAI/TSP framework. TRAI's consumer guidance makes consent and registered preferences relevant to commercial communication; universal exemptions are not assumed and sender-category requirements must be checked for each use case. See Telecom Regulatory Authority of India. Combine with our Bulk SMS Service for statements and alerts. Our banking SMS solutions are purpose-built for this.
User registration, checkout OTPs, order confirmations, and delivery updates. Works directly with Shopify, WooCommerce, and custom stacks. Reduces cart abandonment caused by slow or failed verification steps.
Appointment confirmation, lab report access, and secure patient portal login all via approved OTP templates. Relevant for clinics, hospital chains, and diagnostic labs handling sensitive health data. See our OTP for patient verification and healthcare SMS solutions.
Enrollment verification, exam registration OTPs, and fee payment confirmation. Our education sector templates are pre-approved and ready to deploy saving weeks of DLT approval time.
KYC verification, wallet top-up confirmations, micro-investment approvals, and loan processing workflows. Per-message delivery reports support the audit trail fintech teams need; delivery time depends on operator/network conditions and destination availability.
Driver verification OTPs, delivery confirmation codes, warehouse access authentication, and fleet management 2FA. E-commerce OTP SMS for last-mile delivery confirming POD, securing handoffs, and preventing fraud at every touchpoint across the supply chain.
Employee system access, internal approval workflows, and SaaS 2FA for thousands of concurrent users. Our SMPP connectivity option is purpose-built for enterprise-scale login verification volumes. See our OTP authentication API for SaaS platforms for login-specific integration details.
Login OTPs that hold up during festival-rush and eclipse-event traffic spikes, when signup volume multiplies overnight and a delayed code costs a lost consultation. See our OTP authentication for astrology apps.
Signup and login OTPs that confirm control of the registered mobile number — a first trust signal for profile authenticity, before photo and document verification. See our OTP verification for matrimony platforms.
Low-latency OTP for gaming login and account verification, keeping game studios and esports platforms ahead of signup spikes on tournament and patch-release days. See our OTP for Gaming & Esports.
Hundreds of SMS providers exist in India. Most offer the same infrastructure with different logos. Here's what genuinely differentiates our service things our clients tell us matter most.
How MetaReach stacks up against typical OTP SMS providers in India on the criteria that actually affect delivery and cost.
| Criteria | MetaReach | Typical OTP SMS Providers in India |
|---|---|---|
| Delivery Speed | Per-message delivery reports; timing depends on operator and network conditions | Varies; some providers route OTPs through multiple aggregator hops |
| Pricing Transparency | Volume slabs listed openly, from ₹0.12/SMS + GST | Pricing often quote-only, minimums common |
| DLT Registration Support | Onboarding assistance; any applicable charges are communicated before processing | Support and charges vary by provider |
| OTP and Promotional Traffic Handling | Routing depends on the configured service and applicable TSP requirements | Routing practices vary by provider |
| Voice / WhatsApp / RCS Fallback | Included on the same account | Usually a separate product or provider |
| API Access | OTP SMS API access and integration support; SMS usage follows the applicable messaging plan | Often gated behind a sales call or trial limit |
Evaluating providers for fintech, banking, or e-commerce OTPs in 2026? See our full OTP Pricing breakdown, or read OTP vs Normal SMS differences before you switch.
From fintech startups to enterprise banking platforms — businesses that can't afford authentication failures choose MetaReach.
“We switched to MetaReach after our previous OTP provider was causing 8–12 second delivery delays. The difference was immediate — our checkout completion rate went up by 14% in the first month.”
“MetaReach handled our entire DLT registration — entity setup, sender ID, template approvals — within a few hours. No back-and-forth, no confusion. We were live and sending OTPs the same day.”
“The Voice OTP fallback was a game-changer for us. We serve patients in Tier-2 cities where SMS sometimes fails. The automatic voice call recovers verifications that used to fail — our doctors and patients both noticed the improvement.”
OTP SMS uses our volume slabs — ₹0.40/SMS at 5,000 down to ₹0.12/SMS from 1 lakh, plus GST — with no setup fee and no surprises. Credits are valid for 12 months. View OTP SMS pricing plans →
Buy credits, use them whenever you need no expiry pressure. Ideal for early-stage startups testing their product or businesses with unpredictable SMS volumes.
Pre-purchase SMS credits at discounted rates. The more you send, the lower your per-message cost. Most growing businesses find the bulk packs offer the best value by month 2.
For platforms sending 10 lakh+ OTPs per month. Includes SMPP connectivity, dedicated routes, SLA terms agreed in your contract, priority support, and custom pricing. Talk to our team for a tailored quote.
Trial access may be available for eligible business accounts. Contact MetaReach to confirm current trial availability, credits and onboarding requirements before integration.
OTP SMS pricing in India: MetaReach charges ₹0.40 to ₹0.12 per OTP SMS depending on volume, plus GST. No setup fee. MetaReach can assist with applicable DLT onboarding; any applicable onboarding or service charges are communicated before processing. Contact us for a custom quote.
OTP delivery time: Delivery depends on operator/network conditions, routing, DLT configuration, destination availability and other telecom factors. OTP SMS should use the DLT configuration and content-template category applicable to the sender/entity type, communication purpose, and current TSP/DLT requirements. See full SMS pricing →
Every OTP you send gets a message ID. Use it in your dashboard or through the Delivery Report (DLR) API to see exactly what happened to each code, number by number.
The OTP has been accepted by the gateway and handed to the operator. Delivery time --- means the handset has not confirmed receipt yet.
The operator has confirmed the SMS reached the handset, with a timestamp you can log against the login or transaction attempt.
The message could not be delivered, for example a switched-off or invalid number. Use this status to trigger a resend or a voice OTP fallback.
Per-number delivery status and timestamps give fintech, banking and healthcare teams a record of when each verification code was sent and received.
The OTP SMS API uses plain HTTPS GET requests authenticated with your API key, so you can call it from any language, Postman or cURL.
| Endpoint | What it does | Key parameters |
|---|---|---|
GET https://sms.metareach.in/vb/apikey.php | Send an OTP (single or multiple numbers) | apikey, senderid, number, message, optional templateid |
GET https://sms.metareach.in/vb/http-dlr.php | Get delivery status for a sent message | apikey, msgid |
Every sender ID and message template must be registered on DLT before you send. Keep your API key on your server and never expose it in browser or app code.
Straight answers to the questions we hear most often from businesses evaluating our service.
An OTP SMS service delivers a One-Time Password to a user's mobile number whenever they need to verify their identity for login, payment, registration, or another sensitive action. The OTP arrives as a standard SMS and typically expires within a few minutes. MetaReach provides OTP SMS API and messaging services with support for applicable DLT registration, sender-header and content-template requirements. OTP delivery time depends on operator/network conditions, routing, DLT configuration, recipient availability and other telecom factors.
Transactional, service and promotional communications serve different purposes under India's commercial communication framework. Promotional communication is marketing-oriented, while transactional or service communication is associated with applicable transaction, service, security or customer-related use cases. OTP is a use case and should not automatically be assigned to one universal DLT content-template category. The applicable category depends on the sender/entity type, purpose of communication, recipient relationship or consent where applicable, and current TSP/DLT requirements. Businesses should follow the applicable recipient-preference, consent, sending and operational requirements for the communication category being used. TRAI distinguishes communication types and says sender requirements apply to OTP, transactional, service and commercial messages. https://www.trai.gov.in/advice-to-senders?utm_source=chatgpt.com
Trial access may be available for eligible business accounts. Contact MetaReach to confirm current trial availability, credits and onboarding requirements before integration.
It's a simple HTTPS API: your backend sends a GET request with your API key, the recipient's mobile number, your applicable DLT-registered sender header and registered content-template configuration. The gateway returns a message ID that you use with the Delivery Report API to track each OTP. We have ready-made code samples in PHP, Python, Node.js, Java, and .NET, plus a Postman collection. Integration time depends on the application's backend, authentication flow and implementation requirements. MetaReach provides API documentation and implementation support to help developers complete the integration efficiently. Full API documentation is here.
2FA (two-factor authentication) adds a second verification step after the user enters their password. An OTP is sent to their registered mobile; they enter it to complete login. Our platform supports the 2FA workflow via the REST API. Voice OTP can be configured as an additional authentication channel or fallback option where appropriate, subject to the application's workflow and applicable telecom requirements.
MetaReach assists with the applicable DLT onboarding process, including Principal Entity registration guidance, sender-header registration and content-template registration. Processing and approval timelines depend on document completeness and the relevant DLT/TSP platform. Any applicable onboarding or service charges are communicated before processing. For businesses that haven't gone through this before, we've written a complete DLT guide for 2026 that explains every step.
OTP SMS delivers the one-time code as a text message; Voice OTP can be configured as an additional authentication channel or fallback option where appropriate, subject to the application's workflow and applicable telecom requirements.
DLT requirements apply to commercial SMS traffic in India, including OTP SMS. Businesses should complete the applicable Principal Entity, sender-header and content-template requirements. The applicable content-template category depends on the sender/entity type, communication purpose, use case and current TSP/DLT requirements. MetaReach can assist with the applicable DLT onboarding process.
Trial access may be available for eligible business accounts. Contact MetaReach to confirm current trial availability, credits and onboarding requirements. DLT onboarding follows applicable DLT/TSP processes; processing times depend on document completeness and platform requirements.
Practical guides and comparisons for teams making decisions about their messaging infrastructure.
Not all SMS messages are the same. Here's why OTP routes are fundamentally different from regular bulk SMS and why it matters for your business.
Read article DLT for OTPEntity registration, sender headers, template variables, and the PE-TM binding step most businesses miss — everything needed to get OTP templates DLT-approved.
Read article DeliveryHow automatic Voice OTP fallback catches the OTPs that SMS alone misses — trigger conditions, retry timing, and API setup to recover more OTPs.
Read article DLT GuideEverything you need to know about TRAI's DLT requirements who needs to register, what the process looks like, and how to avoid the common pitfalls.
Read article ComplianceSending SMS without DLT compliance is a regulatory risk and messages simply don't get delivered. Here's what changed and what you need to do.
Read article ComparisonFor OTPs and authentication, SMS consistently outperforms WhatsApp on reach and reliability. Here's the breakdown by use case.
Read article How-ToMost SMS delivery failures trace back to DLT setup errors. This guide covers the top mistakes businesses make and how our team can help you avoid them.
Read article Deep DiveThe PE-TM binding chain is why some messages go through and others don't. A plain-language explanation for business owners and developers.
Read articleFrom startups to enterprises — brands that grow with MetaReach
Guides, OTP, transactional, DLT registration & city coverage — everything about bulk SMS in India
Send your first bulk SMS campaign with the right setup and routing for your use case. Contact MetaReach for current commercial terms and onboarding guidance.
