Aadhaar OTP is used for authentication on dozens of services: the Income Tax portal, DigiLocker, EPFO, bank KYC, SIM activation, PM-Kisan, Ayushman Bharat, and property registrations. When the OTP does not arrive, it blocks everything. You cannot verify your identity and you are stuck.
This guide provides a systematic approach to diagnose and fix the issue, starting from the most common cause (wrong mobile number) to the least common (UIDAI server outage).
Also see: Aadhaar authentication failed (fingerprint, iris, face, Error 330), DigiLocker Aadhaar verification failed, and Update mobile number on Aadhaar when the registered SIM is gone.
Why OTPs Fail: Complete Cause Table
| Cause | How Common | How to Fix | Time to Fix |
|---|---|---|---|
| Wrong/outdated mobile number on Aadhaar | Very common | Update at Aadhaar Seva Kendra | 3-7 days for new number to activate |
| Phone inbox full | Common | Delete old messages | Instant |
| Poor mobile network / dead SIM | Common | Check signal, restart phone, move to window | Instant |
| Phone spam filter blocking OTP messages | Common (Xiaomi, Samsung, realme) | Check spam folder, whitelist UIDAI sender | Instant |
| UIDAI server overload during peak hours | Occasional | Wait and retry during off-peak hours | 30-60 min |
| Requesting too many OTPs rapidly | Occasional | Wait 15-30 minutes, request only one | 30 min |
| Entered old OTP after requesting new one | Occasional | Always use the most recent OTP only | Instant |
| Carrier-level SMS routing delay | Rare | Wait 5-10 min, try TOTP instead | 10 min |
| DND/TRAI blocking transactional SMS | Very rare | Does not usually affect government SMS | N/A |
Step 1: Verify the Registered Number
This is the first and most important check. When you request an OTP, the portal shows the last 4 digits of the registered mobile number (e.g., "OTP sent to xxxxxx1234").
Check if these digits match your current phone number.
If the number is wrong or belongs to an old SIM:
-
Get a replacement SIM first (if possible). If you still own the same phone number but lost the SIM, getting a replacement SIM from your telecom provider (Jio, Airtel, Vi, BSNL) is much faster than updating Aadhaar. Visit your nearest store with an ID proof and you can get a replacement SIM within 24 hours.
-
If the number belongs to a completely different SIM you no longer have: You must update your Aadhaar mobile number at an Aadhaar Seva Kendra (enrolment centre). This requires a physical visit with biometric verification (fingerprint + iris).
See our detailed Aadhaar mobile number update guide for the step-by-step process.
IMPORTANT
If you lost the SIM card registered with Aadhaar, get a replacement SIM from your telecom provider with the same phone number. This is much faster (24 hours) than updating Aadhaar (3-30 days).
Step 2: Basic Phone and Network Checks
Before blaming UIDAI servers, rule out phone-side issues:
-
Check mobile signal: Ensure you have at least 2 bars of network signal. SMS delivery requires basic cellular connectivity. Move to a window or open area if you are indoors or in a basement.
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Restart your phone: A simple restart often fixes SMS delivery issues caused by temporary network registration problems. Turn off the phone completely, wait 30 seconds, and turn it back on.
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Check SMS inbox space: If your inbox is full (common on phones with years of accumulated messages), new SMS cannot be received. Delete old messages, especially media-heavy ones.
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Check spam/blocked messages folder: This is the hidden culprit on many phones:
- Xiaomi/Redmi/POCO: Messages app > More > Spam messages
- Samsung: Messages app > Three dots > Spam messages
- realme/OPPO: Messages app > Spam or Blocked tab
- OnePlus: Messages app > Archived and Spam
- Pixel/Stock Android: Google Messages > Spam & Blocked
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Disable SMS blocking apps: Apps like Truecaller, Hiya, or carrier-specific spam blockers can intercept, delay, or silently filter OTP messages. Temporarily disable them and try again.
-
Check if your SIM is active: Dial any number or send a test SMS to confirm your SIM card is working. An expired or suspended SIM will not receive any messages.
TIP
Do not spam the "Resend OTP" button. If the first OTP does not arrive, wait at least 10-15 minutes before requesting another. Requesting multiple OTPs rapidly triggers rate-limiting on the UIDAI server. Worse, each new OTP request invalidates all previous OTPs, so if the delayed first OTP finally arrives, it will no longer work.
Step 3: Use mAadhaar TOTP as an Alternative
If SMS is unreliable, you can bypass it entirely using the TOTP (Time-based OTP) feature in the mAadhaar app. This is the most reliable workaround.
How to set up TOTP:
- Download the official mAadhaar app from Google Play Store or Apple App Store. Only download the one published by UIDAI (look for the government emblem).
- Open the app and register your Aadhaar profile. This one-time setup does require an SMS OTP. If you cannot get even this single OTP, you must fix the mobile number first (Step 1).
- Once registered, tap on TOTP Generator.
- The app generates an 8-digit OTP that refreshes every 30 seconds.
- Enter this TOTP on the portal requesting Aadhaar OTP. Most government portals accept TOTP:
| Portal / Service | Accepts TOTP? |
|---|---|
| Income Tax e-Filing | Yes |
| DigiLocker | Yes |
| EPFO Member Portal | Yes |
| Bank eKYC | Depends on the bank's integration |
| Telecom SIM activation | Usually No (requires SMS OTP) |
| PM-Kisan | Yes |
| Passport Seva | No |
Key advantages of TOTP:
- Works even when you have zero mobile network (airplane mode, basement, rural area)
- No SMS delivery delay. The code is generated instantly on your phone.
- Not affected by spam filters, DND, or carrier routing issues.
WARNING
TOTP is valid for only 30 seconds. Have the portal ready and the OTP field visible before you open the TOTP generator in the mAadhaar app. Enter the code immediately.
Step 4: Retry During Off-Peak Hours
UIDAI OTP servers handle over 100 million authentication requests per month. They can become overwhelmed during:
- Tax filing season (June-July): Millions use Aadhaar OTP for ITR e-verification
- Government scheme enrollment drives (Ayushman Bharat, PM-Kisan registration)
- Working hours (10 AM - 4 PM on weekdays): Banks and offices process KYC
- Month-end salary processing: Companies batch-process EPF KYC
Best times to try: Early morning (6-8 AM), late evening (8-11 PM), or Sunday mornings.
Step 5: Use Biometric Authentication at Physical Counters
If you are at a bank, telecom shop, or CSC (Common Service Centre) and the OTP is simply not working:
- Ask the operator to switch to biometric authentication (fingerprint or iris scan).
- Biometric auth does not require any OTP or SMS.
- If biometrics are locked, unlock them first using the mAadhaar app or MyAadhaar portal. See our biometric lock guide.
Step 6: Contact UIDAI Support
If none of the above works after 24 hours and you have confirmed the mobile number is correct:
- UIDAI Helpline: Call 1947 (toll-free) and select the OTP/authentication option
- Email: File a query at uidai.gov.in under the grievance/feedback section
- Visit an Aadhaar Seva Kendra for in-person assistance
Common Scenarios and Solutions
| Scenario | What is Happening | Solution |
|---|---|---|
| OTP received but expired by the time I enter it | You took more than 10 minutes | Enter the OTP within 2-3 minutes. Have the portal open and ready. Do not switch apps. |
| Getting OTP for a different service than what I requested | UIDAI sends one OTP for all pending requests within a time window | Use the latest OTP received. Ignore older ones. |
| Family member's OTP coming to my phone | Their Aadhaar is registered with your mobile number | They need to update their Aadhaar mobile to their own number at an enrolment centre. |
| OTP works on Income Tax portal but not DigiLocker | The specific service portal may have its own issues | Check DigiLocker's official Twitter or helpline for outage notifications. |
| I receive OTP but the portal says "invalid" | You may have accidentally entered an older OTP (from a previous request) | Request a single fresh OTP and enter only that one. |
Related Guides
- How to Update Mobile Number on Aadhaar
- How to Lock or Unlock Aadhaar Biometrics
- DigiLocker Aadhaar Verification Failed
- Aadhaar Authentication Failed
Need more help?
For more information, open the Aadhaar Help hub, read our other Identity & KYC guides, or try our calculators.