GST Documentation for Facility Purchases: A Practical Guide

A GSTIN typed wrongly on a purchase order, an invoice with no delivery record behind it, a credit note that did not reach the books: each one delays payment or puts an input credit claim in doubt. This guide walks through the trail of documents each purchase should leave, so finance can trace any invoice back to an approved request.

The trail every purchase should leave

Think of each purchase as a chain of five links: the purchase order (PO), the supplier’s delivery challan, your goods received note (GRN), the tax invoice, and the payment record. Credit or debit notes, and an e-way bill for goods movement, attach to the chain where they apply. If a link is missing, you will feel it at month-end reconciliation or during an audit, which is when it is hardest to fix.

What a tax invoice should show

Ask suppliers to issue invoices with the fields below. Exact requirements are set by the GST rules and vary by type of supply, so confirm current rules with your CA.

• Supplier details: legal name, address and GSTIN.
• Recipient details: your legal entity name, billing address and GSTIN, exactly as on your registration. If you hold more than one registration, the PO must say which one is being billed.
• Invoice number and date: a unique number and the date of issue.
• Description with HSN or SAC: HSN codes describe goods and SAC codes describe services. Line descriptions should be close enough to your PO to be matched at a glance.
• Quantity, unit and taxable value for each line.
• Place of supply: this drives which tax applies. Where goods are billed to one location and delivered to another, confirm with your CA how it is determined.
• Tax split: CGST and SGST where the supply is within one state, IGST where it is between states. The split shown should be consistent with the place of supply.
• Total invoice value.

Three-way match: PO, delivery record and invoice

Before you release payment, check that three documents agree: what you ordered, what arrived, and what you are being billed for.

When the three do not agree, resolve it at document level. If a shortfall was received, ask for a corrected invoice or a credit note rather than paying in full and chasing later. If the price differs from the PO, get the difference explained in writing before the invoice enters your books. A well-written RFQ makes matching easier, because the PO inherits itemised specifications and units.

E-way bills, e-invoices, credit and debit notes

E-way bill. For movement of goods, an e-way bill is generally needed when the consignment value is above ₹50,000, with exemptions for certain goods and situations. Who generates it, and when, depends on the circumstances, so confirm current rules with your CA. In practice, ask the supplier to quote the e-way bill number on the delivery record so it sits in the same file as the challan.

E-invoicing. Some suppliers must report their invoices through the government’s e-invoicing system, where applicable to the supplier. If yours is one of them, the invoice you receive should carry the e-invoice details. Ask each supplier during vendor onboarding whether it applies to them, and confirm with your CA what you should check on receipt.

Credit and debit notes. Corrections after invoicing, such as a rate difference, returned or rejected goods, or a short supply, are documented through credit or debit notes that refer to the original invoice number. Insist on the note rather than an informal adjustment in the next bill. Informal adjustments leave your books and the supplier’s return data disagreeing.

Input tax credit: the conditions in general terms

Whether you can claim input tax credit (ITC) on a purchase depends on conditions set in the law. In general terms:

• You hold a valid tax invoice, or another prescribed document, for the purchase.
• The goods or services have actually been received. Your GRN or completion sign-off is the evidence.
• The supplier has filed their return, and the tax appears against your GSTIN in your auto-populated return data.
• Payment and other conditions apply, including time limits and categories where credit is restricted.

The details and limits change, so confirm current rules with your CA. One related point on payments: where you buy from MSME suppliers, payment-term rules can affect your tax deduction; confirm with your CA before you agree payment terms.

Monthly reconciliation and record retention

Reconcile your purchase register against the auto-populated return data every month rather than at year-end. The usual mismatches are an invoice you booked that the supplier has not reported, a wrong GSTIN on the invoice, an invoice booked in a different period from the one the supplier reported, a credit note in your books but not theirs, and a value difference. Each is easier to fix while the transaction is fresh and the supplier’s accounts team remembers it.

Keep the full trail together, filed by invoice number: PO, challan, GRN, invoice, e-way bill, credit or debit notes and payment proof. How long records must be retained is set by law, so confirm the current period with your CA, and store them so that one search retrieves the whole set.

How SupplycZar can help

For recurring supplies and MRO items, send us your billing entity name and GSTIN, the delivery site and your PO reference with each requirement, so the paperwork can be matched to your records. Invoice format, scope and specifications are confirmed against your requirement. See MRO procurement and recurring facility supplies, or send a requirement through our RFQ form.