Last updated: 17 September 2026
Quick Answer: GST portal OTPs go only to your registered mobile number and email, so an old number is fixed through a non-core amendment. If you can log in, edit the contacts in that amendment and verify the new mobile and email by OTP; it's auto-approved. If you can't log in, your jurisdictional tax officer can update them.
If you're looking up how to change mobile number in GST portal records because OTPs have stopped arriving, first check where the one-time password (OTP) from the Goods and Services Tax (GST) portal is going. Your route then depends on whether you can still log in.
Overview
| Point | What applies |
|---|---|
| Where OTPs go | The registered mobile number and email |
| Change route (can log in) | Services > Registration > Amendment of Registration Non-Core Fields |
| OTP for the change | Sent to the new mobile and email; one common OTP or two, by tab |
| Officer approval | None; it's auto-approved |
| Change route (locked out) | Your jurisdictional tax officer |
| Government fee | None; the amendment has no payment step |
Why is the GST portal OTP not reaching you?
Usually it's going to an old or wrong mobile and email, or the portal doesn't trust your login. It's also sent to the registered email, so check that inbox first.
| What you notice | Likely reason | What to do |
|---|---|---|
| Nothing arrives on your phone | The registered number is old, or a consultant's | Check the registered contact (below), then change it |
| Email OTP arrives, SMS doesn't | Text delivery blocked or delayed | Use the email OTP; check your plan allows SMS |
| Login fails entirely from abroad | The GST portal allows login only from India | Log in from India |
| Aadhaar authentication OTP missing | It goes to your Aadhaar-linked contacts | Check the number linked with Aadhaar |
The GST portal's login FAQs list these reasons; the Aadhaar case is explained in our guide to Aadhaar authentication for GST registration. Still applying for a GST Identification Number (GSTIN)? The first-page OTPs go to the mobile and email typed on the form, so refill that page if one was wrong. Once submitted, track the application with your Application Reference Number (ARN).
How do you check which mobile number is registered?
After logging in, open My Profile > Address and Contacts > Authorized Signatory; a red dot marks the primary signatory. Can't log in? The SMS or email that brought your GSTIN, login details or last ARN went to the registered contacts.
How do you change the mobile number in the GST portal?
You file a non-core amendment and verify the new mobile and email by OTP, which needs a login. The GST portal's non-core amendment manual gives these steps.
- Log in at gst.gov.in and go to Services > Registration > Amendment of Registration Non-Core Fields.
- Open the tab that matches your case (table below) and click Edit.
- Enter the new mobile number and email ID, then click Save.
- Enter the OTP sent to the new contacts. It's valid for 10 minutes.
- On the Verification tab, tick the declaration, pick the signatory and place, and submit with an electronic verification code (EVC) or a digital signature certificate (DSC).
| Your case | Tab to edit | OTP you receive |
|---|---|---|
| Proprietor or partner is also the authorised signatory | Promoter/Partner | Two OTPs, one on each new contact |
| A separate authorised signatory (common in companies and LLPs) | Authorized Signatory | One common OTP on both new contacts |
This is also how to change email ID in GST portal records. You can't file it while a withdrawal application (Form REG-32) is pending.
What if you can't log in to the GST portal at all?
Approach your jurisdictional tax officer, who can enter new contact details and reset your password. "Forgot Username" and "Forgot Password" won't help; both send their OTP to the old contacts. First, try a browser you've used to log in before; trusted devices skip the OTP.
The officer route is set out in a Finance Ministry release on changing contacts through the tax officer (14 June 2018) and the GST portal's known-issues guide:
- Find your jurisdiction on your GST registration certificate.
- Take documents proving your identity and business details.
- The officer checks you're a stakeholder or authorised signatory for that GSTIN.
- The officer enters your new email and mobile and resets the password.
- A username and temporary password reach the new email. Use "First time login" on gst.gov.in, then set your own.
It was meant for taxpayers registered with a consultant's phone and email. It doesn't list documents, so ask the office first. For a portal fault, call the GST helpdesk on 1800-103-4786.
How do you change the authorised signatory in GST to a new person?
Add the new person as a signatory, then make them primary, through two non-core amendments. The Central Board of Indirect Taxes and Customs sets out this order.
- Add the new authorised signatory, with their own mobile and email.
- Submit from the Verification tab and wait about 15 minutes.
- Log in again, untick the old primary signatory and tick the new one.
- Replace the pre-filled old mobile and email with the new ones, then submit.
The new signatory needs a photo (up to 100 KB) and proof of appointment (up to 1 MB), such as an authorisation letter or board resolution. When you submit with EVC, the OTP goes to the new contacts.
How long does a non-core amendment in GST take?
A non-core amendment in GST is auto-approved once filed, with an acknowledgement due within 15 minutes. The ARN goes by SMS and email to the primary authorised signatory. No officer reviews it, unlike a change of business address or legal name.
Can you get help setting up GST contact details correctly?
Yes, when you register. Amendments are always filed on the GST portal under your own login. For a new GSTIN, get GST registration done with guided help from Jaagruk Bharat, a private helper that files it with you.
What mistakes should you avoid when changing GST contact details?
Four slips cause most repeat trouble:
- Dropping the old SIM first. Change the contacts while the old number still works. After that, you'll need the tax officer.
- Letting a consultant use their own number. OTPs then go to them, not you. Keep your own mobile and email on the registration.
- Clicking Save without the new phone and inbox ready. The OTP lapses after 10 minutes.
- Paying a "government fee" for the change. The amendment has none; see what GST registration and amendments cost.
