> ## Documentation Index
> Fetch the complete documentation index at: https://docs.erp.arukz.com/llms.txt
> Use this file to discover all available pages before exploring further.

# GST tax invoices: HSN, CGST, SGST and IGST

> How ARUKZ ERP builds a GST tax invoice from the sales order: both GSTINs, place of supply, HSN or SAC, CGST and SGST or IGST from the state, amount in words.

A GST tax invoice in ARUKZ ERP is made from the sales order, so the customer, items, quantities and prices are already on it, and the system adds the GST detail: your GSTIN and the customer's, the place of supply, an HSN or SAC code on every line, CGST and SGST or IGST at the right rate, and the total in words. You do not pick the tax type on each invoice. It follows the customer's state.

## What prints on the invoice

> [card] Both GSTINs
>
> The title **Tax Invoice**, your GSTIN and the customer's GSTIN.

> [card] Place of supply
>
> The customer's state, with its state code.

> [card] HSN or SAC on every line
>
> Entered once on the product, printed on every invoice. The field takes 4, 6 or 8 digits.

> [card] Tax and total in words
>
> CGST and SGST or IGST with the rate and amount for each, the total in words, and amounts in the Indian format such as ₹1,25,000.00.

## CGST and SGST, or IGST

Each product carries a GST rate. If the customer is in your state, the invoice splits that rate into CGST and SGST. If the customer is in another state, it charges IGST at the full rate. Purchases follow the same rule.

For an 18% item sold for ₹9,000:

| Customer is in | Tax on the invoice | Total |
| - | - | - |
| Your state | CGST 9% ₹810 + SGST 9% ₹810 | ₹10,620 |
| Another state | IGST 18% ₹1,620 | ₹10,620 |

If a line carries a 5% item and an 18% item, they stay as two rates on the invoice and in the returns. ARUKZ ERP reads the rate from the tax line, never by dividing the tax by the value.

## Raise your first GST invoice

**1. Check your company and customer**

Your company needs its GSTIN and state. A registered customer needs a GSTIN and a state on their address.

**2. Add HSN codes and rates to products**

Put the HSN (goods) or SAC (services) code and the GST rate on each product once.

**3. Create the invoice from the sales order**

Confirm the sales order, deliver the goods, and create the invoice from the order. The GST detail fills itself in.

**4. Post and send**

Post the invoice, print or download the PDF, and if you like open WhatsApp with a ready-written message to the customer from the invoice.

> [!TIP]
>
> A new workspace already has rupees, a chart of accounts, GST taxes for sales and purchases and the inter-state rule that switches to IGST. You do not set up taxes before the first invoice. See [First steps](https://docs.erp.arukz.com/get-started/first-steps.md).

## Credit notes and the returns

A credit note is made from the invoice it corrects and carries the same GST detail. Posted invoices and credit notes feed the outward register and GSTR-1 straight away, sorted into B2B, B2C large, B2C small, credit notes, exports and the HSN summary. See [GST returns](https://docs.erp.arukz.com/gst/returns.md).

When an invoice is posted, ARUKZ ERP fixes the customer's GST details on it: their GSTIN, state and GST treatment (regular, unregistered, SEZ, export or deemed export). Editing the contact later does not change an invoice already posted. Posting it again takes a fresh copy.

## E-invoice JSON

For a posted invoice to a business customer, the **E-invoice JSON** button downloads the invoice in the government e-invoice format. Before it builds the file, ARUKZ ERP checks what the portal rejects most often, such as a missing GSTIN, address or HSN code, and tells you what to fix. You then upload the file on the Invoice Registration Portal. See [E-invoice and e-way bills](https://docs.erp.arukz.com/gst/e-invoice-and-e-way.md).

## What it does not do yet

* It does not send invoices to the IRP or fetch the IRN and QR code itself. You upload the JSON and record the IRN the portal returns.
* It does not hold GST rates by date for each HSN code. When a rate changes, update the product's tax yourself.
* It does not check how many HSN digits your turnover requires. Your CA tells you whether 4 or 6 digits apply.

## Related

> [card] [Sales](https://docs.erp.arukz.com/modules/sales.md)
>
> Quotations, sales orders and deliveries that the invoice comes from.

> [card] [Exports under LUT](https://docs.erp.arukz.com/gst/exports-lut.md)
>
> Export invoices with or without IGST, and the declaration they print.


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