General information, not professional advice. GST rules, rates and due dates change by notification. Check the current position on the GST Portal or with your CA before you act on anything here.
The short version
- Every purchase bill is worth its GST as credit and its value as an expense deduction. A lost bill loses both.
- GST records are to be kept for 72 months from the due date of the annual return for that year, and longer where an appeal is pending.
- Keep the bill itself, not only the payment: a UPI screenshot is not a tax invoice.
- A purchase register supplier-wise with GSTIN and HSN is what a GSTR-2B reconciliation actually runs on.
- Photograph bills as they arrive. The pile at month end is where credit goes missing.
Why the bill matters twice
A supplier's tax invoice does two jobs. It is the document on which you claim input tax credit, and it is the evidence for the expense or the purchase in your books, which is what reduces your taxable profit. Lose it and you lose both, and neither is recoverable by remembering the amount.
Take a ₹1,18,000 purchase at 18%. The credit is ₹18,000 and the cost deduction is ₹1,00,000. A bill misplaced between the delivery and the desk is not a filing problem, it is those two numbers.
What to keep
- Tax invoices from suppliers, with their GSTIN on them
- Bills of supply from composition dealers and for exempt purchases
- Debit and credit notes received
- Delivery challans for goods received without an invoice
- Self-invoices and payment vouchers where you are liable under reverse charge
- Bills of entry for imports
- E-way bills for consignments received
- Bank statements and payment records, which support but do not replace the bill
A screenshot of a UPI payment proves you paid somebody. It does not prove what was supplied, at what rate, by whom, with which GSTIN, so it cannot support a credit.
How long to keep it
GST law requires records to be kept for 72 months from the due date of the annual return for that financial year, which works out at roughly six years and nine months from the year end. Where an appeal, revision or other proceeding is pending, keep them for one year after it is finally disposed of, or the 72 months, whichever is later.
Income tax has its own retention expectations, and your CA may ask you to hold some records longer. When in doubt, keeping a scan costs nothing.
Paper, photo or both
Records may be kept electronically, provided they are authentic and can be produced when asked. In practice the workable rule for a small business is:
- Photograph or scan every bill the day it arrives. Thermal paper fades, and a faded bill is a bill you cannot produce.
- Keep the paper too where it is easy, filed by month, not by supplier. You will look for it by date.
- Back it up. One copy on one phone is not a record-keeping system.
The purchase register
The register is what turns a folder of bills into something usable. Supplier-wise, with:
| Column | Why it is there |
|---|---|
| Supplier name and GSTIN | Matching against GSTR-2B |
| Invoice number and date | The key the portal matches on |
| Taxable value | The expense or purchase figure |
| CGST, SGST, IGST, cess | The credit you are claiming |
| HSN | Classification and rate checking |
| Payment status and date | The 180-day rule |
This is exactly the file a 2B reconciliation runs on, which is why your CA asks for a register and not for a folder.
A routine that survives a busy month
- At the door: photograph the bill before it goes anywhere. One photo, and the fade problem is solved.
- Same day: record the purchase with the supplier, the value and the tax, so stock and the payable move together.
- Weekly: check that every delivery you remember has a bill against it. Missing ones are easiest to chase in the same week.
- After the 14th: compare your register against GSTR-2B and chase the suppliers who have not filed.
- Before payment: confirm the bill exists and matches. Paying against a challan or a WhatsApp message is how bills never arrive.
Bills that file themselves
In AawazAI, photograph a supplier bill and the app reads the items, quantities, GST and totals, verifies the e-invoice QR code where there is one, and shows you a card to confirm. Confirming books the purchase, moves stock, updates the supplier balance and records the tax, and the image stays attached to the entry. At month end, the purchase register comes out supplier-wise with GSTIN and HSN, ready for your CA's reconciliation.
Photograph the bill, confirm the card
AawazAI reads a supplier bill into a purchase entry with the items, GST and GSTIN, keeps the image with the entry, and produces the register your CA reconciles.
Frequently asked questions
How long do I have to keep purchase bills under GST?
For 72 months from the due date of the annual return for that financial year, which is roughly six years and nine months from the year end. Where an appeal or other proceeding is pending, keep them until one year after it is disposed of, if that is later.
Can I keep only digital copies of bills?
Records can be kept electronically provided they are authentic and can be produced when required. Photographing bills as they arrive is sensible in any case, because thermal paper fades and a faded bill cannot be produced.
Is a payment screenshot enough to claim input tax credit?
No. Credit requires a tax invoice or debit note from a registered supplier, and the invoice must appear in your GSTR-2B. A payment record supports the transaction but cannot replace the document.
What is a purchase register?
A supplier-wise list of purchases with GSTIN, invoice number and date, taxable value, the tax split, HSN and payment status. It is the file a GSTR-2B reconciliation runs on, which is why your CA asks for it rather than for a folder of bills.
What happens if a supplier never gives me a bill?
You cannot claim credit and you have weak evidence for the expense. For a registered supplier, ask for the tax invoice before paying. Where you are liable under reverse charge and the supplier is unregistered, you generate a self-invoice yourself.