GST Return Filing Guide for Delhi Businesses

Start with what you are actually filing

Businesses in Delhi routinely tell us they "file GST every month" without being able to name the returns involved. That vagueness is where the trouble starts, because the two main returns do very different jobs and failing one has different consequences from failing the other.

GSTR-1 is your outward supply statement. It reports what you sold, invoice by invoice for business-to-business supplies and in summary for smaller retail sales. It carries no payment. What it does carry is your customers' input tax credit — the moment you file GSTR-1, the invoices flow into your buyers' GSTR-2B and become claimable by them. Filing it late means your customers cannot claim credit on time, which is why B2B buyers chase suppliers about it.

GSTR-3B is the summary return where tax is actually paid. It nets your outward liability against the input tax credit you are claiming and requires the balance to be settled in cash. This is the return that costs you money when it is late, because interest runs on the tax paid late.

GSTR-9 is the annual return, a consolidation of the year's filings, and GSTR-9C is a reconciliation statement required above a prescribed turnover level.

Monthly or quarterly: which cycle applies to you

Depending on your registration type, GST returns are generally filed monthly or quarterly, along with an annual return. Regular taxpayers above the prescribed turnover file GSTR-1 and GSTR-3B every month. Smaller taxpayers can opt into the QRMP scheme — Quarterly Return, Monthly Payment.

The name of that scheme is precise and worth reading carefully. Under QRMP, the returns are quarterly but the payment is still monthly, through a challan in Form PMT-06. Businesses that opt in believing they have nothing to do for two months out of three are the ones who accumulate interest without realising it. There is also an optional Invoice Furnishing Facility (IFF) in the first two months of the quarter, which lets you push B2B invoices to your buyers so they can claim credit without waiting for your quarterly GSTR-1.

QRMP suits a business with modest, steady turnover and few B2B customers. It suits a business with large corporate buyers considerably less well, because those buyers will want their credit monthly and will keep asking for it.

The step that prevents most notices: GSTR-2B reconciliation

If you take one thing from this guide, take this. Input tax credit is available only for invoices that appear in your GSTR-2B — an auto-generated statement built from what your suppliers have filed. Your own purchase register is not the test. If a supplier has not filed their GSTR-1, their invoice does not reach your GSTR-2B, and the credit is not available to you no matter how genuine the purchase or how correct the invoice in your hand.

The practical consequence is that a business claiming credit straight from its purchase ledger will, sooner or later, receive a notice comparing the credit claimed in GSTR-3B against the credit available in GSTR-2B. The difference will be demanded back with interest.

The fix is a monthly discipline rather than a clever technique:

1. Download GSTR-2B for the period as soon as it is generated.
2. Match it against your purchase register, invoice by invoice for anything material.
3. Separate the differences into causes — supplier has not filed, supplier filed under the wrong GSTIN, invoice recorded in the wrong period, or duplicate entry.
4. Chase the non-filing suppliers before the period closes. This is far easier in the same month than six months later.
5. Claim only what reflects in 2B, and carry the rest forward once it appears rather than claiming it early.

Doing this consistently is the single largest difference between a clean GST file and a contested one. Our GST registration and return filing service in Delhi treats this reconciliation as a mandatory step in every filing cycle.

What late filing actually costs

Late fees accrue for each day of delay for each return, under both the CGST and the SGST Act, which is why the effective daily figure is double the rate people usually quote. On top of that, interest applies on any tax paid late in GSTR-3B.

The larger cost is structural. GST returns are sequential: you cannot file for a later period while an earlier one is pending, so a single missed month blocks everything behind it and the fees compound across every blocked return. Prolonged non-filing can also block e-way bill generation — which stops goods moving — and can lead to suspension and eventual cancellation of the registration.

Restoring a cancelled GSTIN and regularising a backlog is substantially more expensive than routine monthly filing. Businesses that fall behind almost never do so because they decided the fees were acceptable; they fall behind because one month slipped during a busy period and the arrears then felt too large to face.

Common mistakes we see in Delhi

• Claiming credit on blocked items. Certain expenses are specifically ineligible under section 17(5) — motor vehicles in most cases, personal consumption, works contract services for immovable property. Claiming them is a reliable trigger for a demand.
• Wrong place of supply. Charging CGST and SGST on an inter-state supply, or IGST on an intra-state one, requires correction and can strand your customer's credit.
• Ignoring reverse charge. Certain inward supplies require the recipient to pay tax. Missing these leaves an unpaid liability that surfaces in reconciliation.
• GSTR-1 and GSTR-3B disagreeing. Outward supply reported in the two returns should tally. Systemic mismatch is one of the most common reasons for an ASMT-10 scrutiny notice.
• Books that do not match the returns. Turnover in your accounts, your GST returns and your income tax return should reconcile. Departmental systems compare them, which is why we handle bookkeeping and reconciliation alongside filing.
• Not issuing credit notes properly. Sales returns and discounts handled outside the GST credit note mechanism leave overstated liability that is difficult to unwind later.

What to keep, and for how long

Keep tax invoices issued and received, credit and debit notes, e-way bills, delivery challans, payment records, and the filed returns with their acknowledgements. Records must be preserved for the period prescribed under the GST law, counted from the due date of the annual return for the relevant year — and in practice we advise clients to keep them longer, because reassessment and appeal timelines can run further out than the base retention period.

Where this connects

GST rarely sits in isolation. The turnover you report should agree with your books and with your income tax return filing — our ITR filing checklist covers what to gather for that. If you are still deciding your business structure, the constitution you choose affects your GST obligations, and our company registration in Delhi NCR page sets out the options.

This article is general guidance current as at the date of publication and is not advice on your specific facts. GST rates, thresholds, due dates and procedures change through notification. Please take advice on your own position before acting.