GST billing software: what it must do and how to choose one
The invoice fields the law requires, how tax is split, the documents beyond the tax invoice and a checklist for choosing software, from the team building ERPStack.
Last updated 21 October 2026
What is GST billing software?
GST billing software creates tax invoices that meet India’s GST rules: it records both parties’ GSTINs, HSN or SAC codes and the place of supply, applies the right rate, and splits tax into CGST and SGST or IGST. Good software also handles credit notes, delivery challans, e-invoices and e-way bills, and keeps the data your GST returns need.
Where ERPStack is today
ERPStack is in development. It is not yet available to download or buy, and the features on this page are planned, not shipped.
Sign upWhat must a GST bill contain?
A GST tax invoice has to carry the particulars listed in CGST Rule 46. Billing software earns its keep by filling most of them automatically and refusing to save an invoice that is missing one.
| Group | What the invoice must show |
|---|---|
| Supplier | Name, address and GSTIN |
| Invoice | Serial number (up to 16 characters, unique in the financial year) and date |
| Recipient | Name, address and GSTIN or UIN if registered; for unregistered buyers with taxable value of ₹50,000 or more, the delivery address and state name and code |
| Items | HSN or SAC code, description, quantity and unit, total value, taxable value after discount |
| Tax | Rate and amount of CGST, SGST or UTGST, IGST and cess |
| Supply | Place of supply with the state name for inter-state supplies, delivery address if different, whether reverse charge applies |
| Sign-off | Signature or digital signature (not needed on electronic invoices under the IT Act); IRN QR code if e-invoicing applies |
The number of HSN digits depends on turnover: 4 digits on B2B invoices for businesses with aggregate turnover up to ₹5 crore, and 6 digits on all invoices above that, under Notification 78/2020-Central Tax (PIB summary). For a printable layout, see the GST invoice format.
How should billing software split CGST, SGST and IGST?
The split depends on the place of supply, not on where the customer is billed. If the supplier and the place of supply are in the same state, the tax is divided equally between CGST and SGST (or UTGST in a union territory). If they are in different states, the full amount is IGST.
| Example: ₹10,000 taxable value at 18% | Intra-state supply | Inter-state supply |
|---|---|---|
| CGST | ₹900 (9%) | — |
| SGST / UTGST | ₹900 (9%) | — |
| IGST | — | ₹1,800 (18%) |
| Invoice total | ₹11,800 | ₹11,800 |
Software should work the split out from the supplier’s state and the place of supply you enter, so the person billing never chooses it by hand. Try different amounts and rates in the free GST calculator.
Which GST rates does billing software need to handle?
Following the 56th GST Council meeting, most goods and services moved to a two-rate structure from 22 September 2025: a standard rate of 18% and a merit rate of 5%, with a special rate of 40% for a small set of de-merit goods and services (PIB release). Some tobacco products stayed on their earlier rates and cess for longer, and special rates such as 3% on gold and 0.25% on rough precious stones continue.
That matters for software in two ways. Item masters need the current rate for each HSN code, and credit notes or amendments for invoices dated before 22 September 2025 still have to use the rate that applied on the original invoice date. Software that stores the rate on each invoice line, rather than looking it up afresh, gets this right.
Which documents besides the tax invoice should it create?
| Document | When you need it | Rule |
|---|---|---|
| Bill of supply | Exempt supplies, or any supply by a composition dealer | Rule 49 |
| Credit note / debit note | Price or quantity changes, returns, discounts after the invoice | Rule 53 |
| Delivery challan | Goods moving without a sale, such as job work or approval basis | Rule 55 |
| E-invoice (IRN) | B2B invoices if turnover crossed ₹5 crore in any year since 2017-18 | Rule 48(4) |
| E-way bill | Movement of goods with a consignment value above ₹50,000 | Rule 138 |
| Proforma invoice | A quote before the sale; not a GST document | — |
Each of these should come from the same item, customer and tax data as the invoice. Re-typing details into a second tool is where most GSTR-1 mismatches start. Invoices for goods are also issued in triplicate and for services in duplicate, each copy marked for recipient, transporter or supplier, under Rule 48.
How do you choose GST billing software?
| Question to ask | What a good answer looks like |
|---|---|
| Does every invoice have all Rule 46 fields? | Missing GSTIN, HSN or place of supply blocks the save |
| Is the tax split automatic? | CGST/SGST or IGST is set from the place of supply |
| Can it generate e-invoices and e-way bills? | From the billing screen, not by exporting files |
| Does it handle multiple GSTINs? | One login for branches registered in different states |
| How are returns prepared? | GSTR-1 data comes straight from invoices, with a reconciliation view |
| Is stock linked to billing? | Selling an item reduces stock without a second entry |
| Can you get your data out? | Full export of invoices, customers and items in open formats |
| Where does the data live? | A clear answer on hosting, backups and access |
Desktop software suits a single counter with no internet dependence. Cloud software suits businesses with more than one location, a remote accountant, or salespeople billing on the move. If you also manage inventory, purchasing or production, compare billing tools with an ERP, because billing alone will soon need connecting to those records.
How will ERPStack handle GST billing?
ERPStack is an ERP for Indian small and mid-sized businesses that Perimattic is building. Billing is its starting point. The plan:
- Tax invoices that will not save without the Rule 46 fields.
- The CGST, SGST or IGST split set from the place of supply.
- Credit notes, delivery challans and proforma invoices from the same records.
- E-invoices with an IRN generated through a GSP, and e-way bills.
- Stock and ledgers updated from the same sale.
Status: ERPStack is in development and none of this is available to use yet. Until it is, the free GST invoice generator covers one-off invoices. Sign up to shape what we build first.
This page is general guidance, not tax or legal advice. Rules and rates were checked on 21 October 2026.
Go deeper on GST billing
GST billing, answered
Is there free GST billing software?
Yes, several vendors offer free plans, usually limited by number of invoices, users or features such as e-invoicing. For occasional invoices you can also use a free GST invoice generator. Before you rely on any free tool, check that it includes every Rule 46 field and lets you export your data.
What is the difference between GST billing software and accounting software?
Billing software creates invoices and related documents. Accounting software records those invoices in ledgers alongside purchases, expenses, payments and bank entries, and produces financial statements. Many products do both; an ERP adds inventory, purchasing and manufacturing on top, all working from the same records.
Does a composition dealer need GST billing software?
A composition dealer cannot charge GST to customers and issues a bill of supply instead of a tax invoice, with a note that the business is a composition taxable person. Any billing software used should support the bill of supply format; a full tax-invoice workflow is not needed.
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