# GST Verification Online: How to Verify a GSTIN | FastKYC

> Verify a GSTIN online to confirm a business is registered and compliant: what the 15 characters mean, how to check it on the portal, and how to automate it.

Source: https://www.fastkyc.com/blog/how-to-verify-gst-online/

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[Blog](/blog/)/[GST & Tax](/blog/topics/gst-and-tax/)

# GST Verification Online: How to Verify a GST Number

Verify a GSTIN online to confirm a business is registered and compliant: what the 15 characters mean, how to check it on the portal, and how to automate it.

[Harsine K U](https://www.linkedin.com/in/harsine), Software Engineer23 September 2026·2 min read

## On this page

1.  [1. What is GSTIN?](#what-is-gstin)
2.  [2. Why is GST verification important?](#why-is-gst-verification-important)
3.  [3. What information can GST verification provide?](#what-information-can-gst-verification-provide)
4.  [4. How to verify GST online](#how-to-verify-gst-online)

GST verification helps you verify a GSTIN and access the available registration details of the associated taxpayer. It provides businesses with a reliable way to confirm GST and registration information before entering into a business relationship.

## [What is GSTIN?#](#what-is-gstin)

GSTIN is a **15-character, PAN-based unique identification number** assigned to entities registered under GST in India. It serves as a unique identifier for registered taxpayers and is commonly included on business documents such as tax invoices and bills of supply.

### Understanding the GSTIN structure

A GSTIN follows a specific format, such as **29ABCDE1234F1Z5**:

-   **First 2 characters:** State or Union Territory code
-   **Characters 3-12:** PAN of the taxpayer
-   **13th character:** Entity or registration number
-   **14th character:** Default character, generally Z
-   **15th character:** Checksum character

Understanding the GSTIN structure can help identify an incorrectly formatted GST number.

## [Why is GST verification important?#](#why-is-gst-verification-important)

GST verification helps businesses validate the GST details provided by customers, vendors, suppliers, and other businesses.

Common use cases include:

-   Vendor and supplier verification
-   Customer onboarding
-   Invoice verification
-   B2B verification
-   Fraud and risk checks

## [What information can GST verification provide?#](#what-information-can-gst-verification-provide)

GST verification can provide key details about a registered taxpayer, including:

-   Legal name
-   Trade name
-   GST registration status
-   Registration date
-   Business address
-   Nature of business
-   Taxpayer type
-   HSN/SAC information

## [How to verify GST online#](#how-to-verify-gst-online)

You can verify a GST number online through the official GST portal or automate the process using a GST verification API.

### 1\. Verify a GST number through the official GST portal

For an single GST check:

1.  Go to the official [GST portal (](https://www.gst.gov.in/)[https://www.gst.gov.in/](https://www.gst.gov.in/)[)](https://www.gst.gov.in/) and open **Search Taxpayer**.
2.  Select **Search by GSTIN/UIN**.
3.  Enter the **15-digit GSTIN**.
4.  Enter the displayed **captcha**.
5.  Click **Search** to view the available GST registration details.

This method is suitable for manually checking individual GST numbers.

### 2\. Verify a GST number using an API

Businesses can automate GST verification using the [GST Verification API](https://www.fastkyc.com/apis/gst-verification/):

1.  Integrate the verification API with your application.
2.  Send the GSTIN in the API request.
3.  Receive the available GST registration details in the API response.

This is useful for customer onboarding, vendor verification, KYC, and automated business verification.

-   GST
-   GSTIN
-   Business verification
-   Vendor onboarding

[Harsine K U](https://www.linkedin.com/in/harsine), Software Engineer

Harsine builds the verification APIs behind FastKYC, covering identity, bank, GST and document checks used by fintechs, banks and enterprises across India.

## APIs related to this article

-   [GST Verification APIVerify a GST number and retrieve the registered business name, address, status and registration details from GST records.](/apis/gst-verification/)
-   [GST Advanced APIEnhanced GSTIN verification with compliance and filing history, promoter details, turnover data and e-invoice applicability for deeper KYB checks.](/apis/gst-verification-advanced/)
-   [GSTIN By Pan APIRetrieve every GSTIN linked to a PAN, with the state and current status of each registration, to see a business's full GST footprint in one call.](/apis/gst-by-pan/)
-   [Contact Details by GST APIFetch the mobile number and email address registered against a GST number, giving you verified contact details for a business you are onboarding.](/apis/gst-to-contact-details/)

## Frequently Asked Questions (FAQs)

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