Capturing the GSTIN

To issue a B2B tax invoice with input tax credit (ITC) for your customer, GST Manager needs the buyer's 15-character GSTIN. The app captures this through four different methods, making it compatible with any Shopify plan.

Storefront cart page → Get GST Invoice block

1. Cart-page block (Theme App Embed)

This is the standard method for most stores. A clean block appears on your cart page where customers can opt in:

1. The customer checks "Get GST Invoice".
2. Input fields appear for GSTIN and Company Name.
3. The customer enters their details and clicks Save.
4. The GSTIN is saved directly to the order as a cart attribute.

How to enable the cart block

1. In Shopify admin, go to Online Store → Themes.
2. Click Customize on your current theme.
3. Click the App embeds icon on the left sidebar (third icon from top).
4. Find Collect Customer GST and toggle it On.
5. Click Save in the top right.

Custom CSS styling

The app embed settings include a Custom CSS textarea so you can adjust fonts, colors, and borders to match your store's branding.

2. Shopify B2B Companies (Pro plan)

If you use Shopify Plus B2B:

1. Enable Use Shopify B2B Companies as canonical GSTIN source in Settings → Other Settings.
2. When a B2B customer places an order, the app automatically reads their GSTIN from the CompanyLocation.taxRegistrationId field in Shopify.
3. The buyer does not need to re-enter their GSTIN on the cart page.

3. Saved customer records

For returning buyers:

• The app remembers GSTINs previously used by a customer.
• In Settings → Other Settings, you can choose to allow buyers to switch between multiple GSTINs, or automatically lock the field to their existing GSTIN.

4. Admin override

If a customer forgot to enter their GSTIN at checkout:

1. Open Apps → GST Manager → Orders.
2. Click on the order.
3. Click Regenerate to update the buyer details and enter the GSTIN manually.
4. A revised tax invoice is generated with the customer's GSTIN.

Supply type classifications

Every order is automatically classified and tagged with a badge in your Orders list:

• B2B — buyer provided a valid GSTIN; eligible for input tax credit.
• B2C Large (B2CL) — inter-state order without GSTIN above ₹2.5 Lakhs.
• B2C Small (B2CS) — order without GSTIN below ₹2.5 Lakhs.
• Export — international orders with zero-rated or exempt supply.

Related pages

• Invoices & credit notes — how invoices are generated
• GST reports — how supply types roll up into GSTR-1
• Settings reference — customer GST preferences
• Quick setup wizard — initial setup