How to Change Mobile Number on GST Portal: Complete Guide

Why is Your Mobile Number Important on the GST Portal?

Your registered mobile number on the GST portal is critical for receiving One-Time Passwords (OTPs) during return filing, e-way bill generation, refund applications, and other compliance activities. An outdated or incorrect mobile number can block you from performing essential GST functions, leading to missed deadlines and penalties.

The Ledger Company provides this comprehensive guide to help you update your mobile number on the GST portal seamlessly.

Who Can Update the Mobile Number?

The process for changing the mobile number depends on whose number is being updated:

Important: Changing the mobile number of a promoter, partner, or director is classified as a core amendment under GST rules, requiring approval from the jurisdictional tax officer. Changes to the authorized signatory's contact details are non-core amendments and are processed automatically.

Step-by-Step: Changing Authorized Signatory's Mobile Number

Follow these steps to update the mobile number of a primary or additional authorized signatory:

Step 1: Log in to the GST Portal

Visit www.gst.gov.in and log in with your GSTIN credentials (username and password).

Step 2: Navigate to Amendment Application

Go to Services → Registration → Amendment of Registration Non-Core Fields.

Step 3: Select the Authorized Signatory Tab

Click on the "Authorized Signatory" tab in the amendment form. You will see the list of current authorized signatories.

Step 4: Edit Mobile Number

Click the Edit icon next to the authorized signatory whose mobile number you want to change. Update the mobile number in the designated field.

Step 5: OTP Verification

An OTP will be sent to the new mobile number for verification. Enter the OTP to confirm the change. A second OTP may be sent to your registered email for dual verification.

Step 6: Submit with DSC or EVC

After OTP verification, sign the amendment application using either:

• Digital Signature Certificate (DSC) — mandatory for companies and LLPs
• Electronic Verification Code (EVC) — available for proprietorships, partnerships, and individuals

Step 7: Confirmation

Upon successful submission, the changes are applied immediately for non-core amendments. You will receive a confirmation SMS on the new number and an email notification.

Step-by-Step: Changing Promoter/Partner/Director's Mobile Number

For promoters, partners, or directors, the process involves a core amendment:

Step 1: Log in and Navigate

Log in to www.gst.gov.in and go to Services → Registration → Amendment of Registration Core Fields.

Step 2: Edit Promoter Details

In the "Promoters/Partners" tab, click edit next to the relevant person and update the mobile number.

Step 3: Upload Supporting Documents

Upload the following documents as applicable:

• Letter requesting the change on company letterhead
• Board resolution (for companies) authorizing the update
• Copy of Aadhaar card of the promoter/partner (for identity verification)

Step 4: Submit Application

Sign and submit the application using DSC or EVC. The application is assigned an Application Reference Number (ARN).

Step 5: Officer Approval

The jurisdictional tax officer reviews the application. The officer may:

• Approve the amendment — changes reflect on the portal within 15 working days
• Reject the amendment — with reasons communicated via the portal
• Seek Clarification — issue a notice requesting additional documents

Common Issues and Troubleshooting

Here are common problems faced while updating mobile numbers on the GST portal and their solutions:

OTP Not Received

• Ensure the new mobile number has active network connectivity
• Check if the number is DND-activated — deactivate DND temporarily
• Wait for 2-3 minutes before requesting a fresh OTP
• Try during off-peak hours (early morning or late evening)

Amendment Application Stuck

• Check the application status under Services → Registration → Track Application Status
• If pending for more than 15 days, escalate through the GST grievance portal
• Ensure all required documents were uploaded correctly

Aadhaar-Linked Mobile Mismatch

If your GST registration is Aadhaar-authenticated, the mobile number linked to Aadhaar may be used for verification. In case of a mismatch, update your Aadhaar-linked mobile number first through the Aadhaar centre before updating on the GST portal.

Important Points to Remember

• Always keep your mobile number and email updated to avoid compliance issues.
• Core amendments (promoter details) take up to 15 working days for approval.
• Non-core amendments (authorized signatory details) are processed instantly after OTP verification.
• You can track the status of your amendment application using the ARN.
• Changes to mobile number do not affect your GSTIN — the registration number remains unchanged.
• Ensure you update the mobile number in all linked systems — e-way bill portal, e-invoicing portal, etc.

How The Ledger Company Can Help

Navigating the GST portal for amendments can be confusing, especially for core field changes that require officer approval. The Ledger Company offers end-to-end GST compliance services including registration amendments, document preparation, follow-up with tax authorities, and portal troubleshooting. Our dedicated GST experts ensure your records stay accurate and up-to-date, so you never miss an OTP or a filing deadline. Reach out to us for hassle-free GST amendment assistance.