GST Portal Login OTP Not Coming? Fix Authentication Issues

Cannot log in to the GST portal because OTP is not arriving? Or facing issues with EVC, DSC, or forgot password? These are common problems faced by lakhs of taxpayers. This guide covers every GST portal authentication issue and how to fix it.

Disclaimer: CitizenNest is an independent platform and is not affiliated with the Government of India or GSTN.

Common GST Login and Authentication Issues

1. OTP Not Received on Mobile or Email

Causes:

• Network congestion or mobile signal issues
• DND (Do Not Disturb) activated on your mobile number
• Mobile number or email registered with GST is outdated
• GSTN server overload during peak hours

How to fix:

1. Wait at least 2-3 minutes — OTPs can be delayed during peak hours
2. Click "Resend OTP" on the portal (you can resend up to 3 times)
3. Check if DND is active — dial 1909 from your mobile to deactivate DND or send "STOP DND" to 1909
4. Check your email spam/junk folder for the email OTP
5. Verify your registered mobile and email: Go to gst.gov.in > Search Taxpayer > Search by GSTIN — your registered details will be partially visible
6. If your mobile number has changed, update it through Services > Registration > Amendment of Registration (you need to be logged in, so use email OTP first)
7. Try during off-peak hours (early morning or late night)

2. Forgot Username or Password

Forgot Username:

1. Go to gst.gov.in > Login > "Forgot Username?"
2. Enter your GSTIN or PAN
3. Verify with OTP sent to registered mobile and email
4. Your username will be displayed and also sent via SMS/email

Forgot Password:

1. Go to gst.gov.in > Login > "Forgot Password?"
2. Enter your username
3. Choose verification method: OTP on mobile/email or answer security question
4. If OTP method: Enter the OTP received on registered mobile and email
5. Set a new password following the password policy:
   • Minimum 8 characters
   • At least one uppercase letter, one lowercase letter, one number, and one special character
6. If you cannot access registered mobile or email, contact the GST helpdesk at selfservice.gstsystem.in

3. TRN (Temporary Reference Number) Login Issues

When to use TRN login: During new GST registration, before your GSTIN is generated.

Common issues and fixes:

1. TRN not accepted: Ensure you are entering the TRN on the correct page — Services > Registration > New Registration > select "Temporary Reference Number (TRN)"
2. OTP not received for TRN login: The OTP is sent to the mobile and email you provided during Part A of registration (not your Aadhaar-linked number)
3. TRN expired: TRN is valid for 15 days only. If expired, you must start a fresh registration
4. "TRN does not exist" error: Double-check the TRN. If the issue persists, the Part A submission may have failed — start a new registration

4. EVC (Electronic Verification Code) Not Working

What is EVC: EVC is used to verify and file returns/applications. It is sent to registered email and mobile.

Common issues and fixes:

1. EVC expired: EVC is valid for only 10 minutes — enter it quickly after receiving
2. EVC not received: Same fixes as OTP not received (check DND, network, spam folder)
3. "Invalid EVC" error: Ensure you are entering the latest EVC — if you requested multiple times, only the last one is valid
4. EVC option not available: For companies and LLPs, EVC is not available for return filing — you must use DSC
5. EVC is available for proprietorship firms with turnover up to ₹5 crore (for return filing)

5. DSC (Digital Signature Certificate) Based Login Issues

When DSC is required:

• Companies and LLPs must use DSC for return filing and certain applications
• Any taxpayer can optionally use DSC

Common issues and fixes:

1. "DSC not detected" error:
   • Install the latest emsigner utility from gst.gov.in > Downloads > emsigner
   • Ensure your DSC dongle is plugged in before opening the portal
   • Check that Java is installed and updated on your system
2. "DSC not registered" error:
   • Register your DSC first: Go to My Profile > Register/Update DSC
   • Upload the public key certificate (.cer file) of the authorized signatory
3. DSC expired:
   • Check the validity of your DSC — typically valid for 2 years
   • Renew with your DSC provider (e.g., eMudhra, Sify, NSDL)
   • Re-register the renewed DSC on the GST portal
4. emsigner not working:
   • Use Google Chrome browser (latest version)
   • Run emsigner as Administrator
   • Disable antivirus temporarily if it blocks emsigner
   • Ensure port 1585 is not blocked by firewall

How to Update Registered Mobile or Email on GST Portal

If your registered mobile number or email is outdated, you cannot receive OTPs. Here is how to update:

1. Log in using any method available (email OTP, DSC, or get help from your tax consultant who has authorized access)
2. Go to Services > Registration > Amendment of Registration (Non-core fields)
3. Update the mobile number and/or email address of the authorized signatory
4. Submit the amendment — OTP will be sent to the new mobile/email for verification
5. The amendment is processed automatically without officer approval (for non-core fields)

GST Portal Browser and System Requirements

Important Tips

1. Always keep your registered mobile number and email updated in GST registration
2. Deactivate DND on your registered mobile to ensure OTP delivery
3. Bookmark the official login page: services.gst.gov.in/services/login
4. Never share your GST login credentials or OTP with anyone
5. For DSC issues, keep the emsigner utility updated and test it before the filing deadline

Frequently Asked Questions

Q1. How many times can I request OTP on the GST portal?

You can request OTP up to 3 times per session. If all attempts fail, wait 30 minutes before trying again.

Q2. Can I use someone else's mobile number for GST OTP?

No. OTP is sent only to the mobile number and email registered with your GSTIN. You must update your registration if the number has changed.

Q3. My DSC is registered but still shows "not detected." What should I do?

Reinstall the emsigner utility, plug in the DSC token before opening the portal, and ensure Java is updated. Also try running Chrome as Administrator.

Q4. Can I log in to the GST portal using Aadhaar OTP?

No. GST portal login uses OTP sent to the mobile and email registered with your GST registration, not Aadhaar-linked mobile. Aadhaar OTP is used only during the registration process.

Q5. What is the GST helpdesk number for login issues?

You can raise a ticket at selfservice.gstsystem.in or call the GST helpdesk at 1800-103-4786 (toll-free).

Q6. I changed my mobile number but cannot log in to update it. What should I do?

Try logging in using email OTP instead. If that also fails, visit your jurisdictional GST office with your registration certificate and ID proof to request a manual update.

Q7. How do I check which mobile number is registered with my GSTIN?

Go to gst.gov.in > Search Taxpayer > Search by GSTIN. The registered mobile and email will be partially displayed (e.g., ******1234).