Most billing mistakes on a GST invoice do not come from the wrong tax rate. They come from one small field that gets picked without much thought. That field is place of supply.

Place of supply decides whether your invoice should charge IGST, or CGST and SGST. Get it wrong, and the mistake does not stay small. It can affect your GSTR 1 reporting, your customer's Input Tax Credit, your e-way bill data, your branch transfer records, and your invoice reconciliation later.

The most common reason this goes wrong is simple. Many teams pick place of supply straight from the customer's billing address, every time, without checking how the goods were actually delivered. This guide will help you fix that habit and build a proper check into your billing process.

• Key Takeaways
• The Mistake Almost Every Team Makes First
• What Place of Supply Actually Means
• How the Tax Type Gets Decided
• Your Checklist Before Raising Any Goods Invoice
• Five Situations, and How Place of Supply Works in Each
• Bill From, Dispatch From, Ship To, and Place of Supply
• Branch Transfers
• Auditing Place of Supply Before You File GSTR 1
• Frequently Asked Questions

Key Takeaways

• Place of supply decides whether your invoice should carry IGST or CGST and SGST.
• Using the billing address as the place of supply every time is one of the most common mistakes in goods billing.
• In Bill to Ship to orders, the place of supply is the buyer's main place of business, not the final delivery address.
• Place of supply errors affect GSTR 1 reporting, the customer's Input Tax Credit, and e-way bill data.
• Five main rules cover most goods supply situations: movement of goods, Bill to Ship to, no movement, installation or assembly, and on board supply.
• A pre-billing checklist and a periodic audit before GSTR 1 filing can prevent most place of supply errors.

The Mistake Almost Every Team Makes First

Before we get into the rules, it helps to know where things usually go wrong. Once you know these, the rules below will make a lot more sense.

• Using the billing address as the place of supply, every single time. The billing address is not always where the goods end up. Goods can be sent somewhere else entirely, handed to a third party, or installed at a completely different site.
• Assuming the delivery state is always the place of supply in Bill to Ship to orders. In these orders, the final delivery state is not always the correct place of supply. You need to check who actually gave the delivery instruction.
• Charging IGST just because the goods crossed a state border. Crossing a border usually does mean IGST, but you still have to compare the supplier location with the place of supply to confirm it.
• Forgetting to check the installation site. If goods are installed or assembled somewhere, that site decides the place of supply, not the billing address.
• Treating a branch transfer like a normal internal move. A transfer between two different GSTINs is not the same as moving stock within one registration.
• Leaving the place of supply off interstate invoices. Rule 46 requires the place of supply and the state name to appear on these invoices.
• Letting a wrong state code slip through. This creates mismatches between the invoice, the e-invoice, and the e-way bill.
• Not updating customer records. If a buyer's GSTIN, state, or ship to address is wrong in your system, that same error will repeat on every invoice you raise for them.

What Place of Supply Actually Means

Place of supply is the location that GST law uses to decide if a sale is interstate or intrastate. For goods, this comes mainly from Section 10 of the IGST Act.

It is not one fixed rule. It depends on how the sale actually happens, such as:

• Whether the goods move from one place to another
• Whether the goods go to a third party on the buyer's instruction
• Whether the goods are supplied without any movement at all
• Whether the goods are installed or assembled at a site
• Whether the goods are supplied on board a train, ship, flight, or vehicle

You need to work this out first. Only then can you decide whether to charge IGST or CGST and SGST.

This single field also touches far more than the tax amount. It affects your GST rate application, your GSTR 1 reporting, your customer's ITC claim, your e-invoice data, your e-way bill data, your state wise reports, your branch transfer accounting, and your audit trail. A wrong place of supply can show the wrong tax type even when your rate and value are both correct.

How the Tax Type Gets Decided

Once you know the place of supply, comparing it to the supplier location tells you the tax type.

Take a supplier in Maharashtra selling to a buyer in Maharashtra, with delivery also in Maharashtra. Here the place of supply is Maharashtra, the same as the supplier, so the invoice should carry CGST and SGST.

Now change just the delivery. If the same supplier sends the goods to a buyer in Gujarat instead, the place of supply becomes Gujarat. Since that is different from the supplier state of Maharashtra, the invoice should carry IGST.

Your Checklist Before Raising Any Goods Invoice

This is the part to keep open while billing. Run through it before you finalise any GST invoice for goods.

Supplier Details

• The correct supplier GSTIN is selected.
• The correct branch or business location is selected.
• The supplier state code matches the GSTIN.
• The Bill From location is correct.
• The Dispatch From location has been checked separately.
• The invoice series belongs to the correct GSTIN or branch.

Buyer Details

• The buyer's legal name is correct.
• The buyer's GSTIN is valid.
• The buyer's state matches their GSTIN state code.
• The Bill To address is correct.
• The customer record is up to date.
• The buyer's registration status has been checked.

Delivery and Ship To Details

• The Ship To location is recorded separately from the Bill To address.
• The delivery address is complete.
• The delivery state and PIN code are correct.
• The Ship To GSTIN has been checked, where it applies.
• The difference between Bill To and Ship To has been reviewed.
• The delivery location has not been used blindly as the place of supply in Bill to Ship to cases.

Place of Supply

• The correct place of supply rule has been identified.
• The normal movement rule has been applied, where it fits.
• The Bill to Ship to rule has been applied, where it fits.
• The installation or assembly rule has been applied, where it fits.
• The no movement rule has been applied, where it fits.
• The on board supply rule has been applied, where it fits.
• The place of supply state name appears on interstate invoices.

Tax Type

• The supplier location has been compared with the place of supply.
• IGST is selected for interstate supply.
• CGST and SGST are selected for intrastate supply.
• CGST and SGST amounts are equal.
• The tax type matches the GSTR 1 treatment.
• The invoice total has been recalculated after the tax type is chosen.

E-Way Bill and E-Invoice Data

• The e-way bill delivery details match the invoice.
• The Dispatch From and Ship To PIN codes are correct.
• The place of supply matches the invoice treatment.
• The IRN data matches the final invoice.
• The vehicle and transporter details have been checked.
• The e-way bill distance and PIN code have been validated.

Five Situations, and How Place of Supply Works in Each

Now that you have the checklist, here is how to apply the place of supply rule to five common situations. Each one comes with a real working example.

Not the Same Thing: Bill From, Dispatch From, Ship To, and Place of Supply

These four fields often get mixed up, but they each mean something different.

Here is a case where all four are different. A company bills from its Mumbai GSTIN, but the goods are actually sent from a warehouse in Pune. The invoice is billed to a customer in Delhi, but the goods are shipped to a party in Jaipur, because the Delhi customer asked for it. In this case, the Bill From is Mumbai, the Dispatch From is Pune, the Bill To is Delhi, the Ship To is Jaipur, and the place of supply is Delhi, since this is a Bill to Ship to case.

Every one of these fields has to be entered correctly and separately across your invoice, your e-invoice, and your e-way bill.

One More Situation Worth Knowing: Branch Transfers

A company transfers goods from its Maharashtra GSTIN to its own Karnataka GSTIN. Even though this feels like an internal move, the two GSTINs can be treated as separate persons under GST. Here, the place of supply is Karnataka, and the invoice carries IGST. This kind of transfer needs to be documented properly and matched against your e-way bills and inventory records, using a tax invoice where the transfer is taxable.

Auditing Place of Supply Before You File GSTR 1

Do not wait until something looks wrong. Build this check into your process every period, before filing.

A simple internal report can help here. It only needs a handful of columns.

How Billing Software Helps

Keeping track of Bill From, Dispatch From, Bill To, Ship To, and place of supply across every invoice is easy to get wrong when it is done manually. Hitech Billsoft applies the correct place of supply rules automatically based on the transaction details you enter, flags mismatches before the invoice is saved, keeps your GSTIN and state records accurate across customers and branches, and generates e-invoice and e-way bill data that is consistent with each invoice. For businesses dealing with regular interstate sales, Bill to Ship to orders, or branch transfers, this removes most of the manual checking that currently falls on your billing team.

Conclusion

Place of supply is not a field to fill by habit. It is the foundation of whether your invoice is GST compliant. Get it right, and your tax type, your return filing, your customer's ITC, and your transport documentation all align. Get it wrong, and the error spreads across every system that touches that invoice.

The checklist in this guide is designed to be used at the billing stage, not after the fact. Run through it consistently, build the audit into your pre-filing process, and most of the common place of supply mistakes simply stop occurring.