Input Tax Credit (ITC) Under GST: Eligibility, Blocked Credits, Reversals & How to Claim It Right

The mechanism that stops GST from taxing tax on tax — and the single most common source of GST notices when it’s claimed wrong

Published: September 11, 2026 · Last updated: September 11, 2026

Input Tax Credit is the credit a GST-registered business gets for the tax it already paid on its purchases, which it can then set off against the tax it owes on its sales. Without it, GST would tax the same value multiple times as goods move through a supply chain — manufacturer to wholesaler to retailer to customer — each one paying tax on a price that already includes the previous seller’s tax. ITC is what keeps GST a tax on value added at each stage, rather than a tax on the whole transaction value every time it changes hands.

How ITC Actually Works

Say a retailer buys stock worth ₹1,00,000 and pays 18% GST on it — ₹18,000 (as ₹9,000 CGST + ₹9,000 SGST, assuming an intra-state purchase). When that retailer sells the goods for ₹1,50,000, they charge the customer 18% GST — ₹27,000. Instead of depositing the full ₹27,000 with the government, the retailer nets it against the ₹18,000 already paid on the purchase, and deposits only the difference: ₹9,000. That ₹9,000 is the tax on the ₹50,000 of value the retailer actually added. The GST calculator on this site handles the CGST/SGST/IGST split for either side of that calculation if you want to check your own numbers.

Conditions to Claim ITC (Section 16, CGST Act)

You can’t claim ITC just because you paid GST on something. Section 16 sets out four conditions, and all four have to be met:

You hold a valid tax invoice (or debit note) from a registered supplier.
You’ve received the goods or services. If goods arrive in instalments, ITC can only be claimed after the last instalment lands.
The supplier has actually paid the tax to the government and reported the invoice, so it shows up in your GSTR-2B.
You’ve filed your own GST return for the relevant period.

That third condition is the one that catches people out most often — your right to the credit depends on your supplier’s compliance, not just yours. If a supplier fails to file or pay, the credit can be denied or reversed on your side even though you did everything right.

Blocked Credits: What You Can’t Claim (Section 17(5))

Some categories of GST paid are permanently ineligible for ITC, regardless of whether the purchase was for business use:

Category	Blocked unless…
Motor vehicles for passenger transport (≤13 seats)	Used for further supply of vehicles, passenger transport, or driving training
Food, beverages, outdoor catering, health/beauty treatment	Used to make the same category of outward taxable supply
Life and health insurance	Government-notified as obligatory for employees, or used to make the same outward supply
Works contract services for construction of immovable property	Used for further supply of works contract services (plant & machinery is an exception)
Goods/services for personal consumption	Never eligible
Membership of clubs, health and fitness centres	Never eligible

Claiming ITC on a blocked category is one of the most common triggers for a GST scrutiny notice, because it’s an easy mismatch for the department’s systems to flag automatically.

When You Have to Reverse ITC

ITC isn’t always permanent once claimed. You’re required to reverse credit already taken in a few specific situations:

Non-payment to supplier within 180 days of the invoice date — if you haven’t paid your supplier (including the GST component) within 180 days, the ITC you claimed has to be reversed, with interest, until you do pay.
Exempt or non-business use (Rule 42/43) — if you use inputs or capital goods partly for exempt supplies or personal purposes, the proportionate credit attributable to that use has to be reversed.
Credit notes from suppliers that reduce the taxable value after you’ve already claimed ITC on the original invoice.
Goods lost, stolen, destroyed, or given as free samples/gifts — ITC on these has to be reversed under Section 17(5)(h).

Reversals are reported in Table 4(B) of GSTR-3B, separate from the eligible credit you’re claiming that period.

Why ITC Claims Get Rejected: The GSTR-2B Connection

Since 2022, ITC eligibility has been tied directly to GSTR-2B — an auto-generated statement showing exactly which invoices your suppliers have reported. If an invoice doesn’t appear in your GSTR-2B (because the supplier hasn’t filed, filed late, or made an error), you generally can’t claim ITC on it that period, even if you’re holding a perfectly valid physical invoice. This is also where e-invoicing matters directly: for businesses above the notified turnover threshold, an invoice that missed the 30-day IRP reporting window isn’t a valid tax invoice at all, which means no ITC on it for the buyer — not a technicality, a hard block.

Reconciling your purchase register against GSTR-2B every month, before filing GSTR-3B, is the single most effective habit for avoiding ITC mismatches and the notices that follow them.

A Worked Example

A furniture retailer in Maharashtra buys raw material worth ₹5,00,000 (intra-state, 18% GST — ₹45,000 as ₹22,500 CGST + ₹22,500 SGST) and pays ₹20,000 in rent with 18% GST (₹3,600, again split CGST/SGST). Total ITC available: ₹48,600. In the same month, the retailer sells finished furniture worth ₹9,00,000 within the state, charging 18% GST — ₹1,62,000 output tax. Net GST payable after offsetting ITC: ₹1,62,000 − ₹48,600 = ₹1,13,400, split proportionately as CGST and SGST. That net figure — not the full output tax — is what actually gets deposited via GSTR-3B.

Quick Questions

Can I claim ITC without a valid invoice?
No. A valid tax invoice (or debit note) from a registered supplier is a strict precondition under Section 16 — no exceptions for informal or cash purchases.

Is ITC available on GST paid on office rent?
Yes, rent for business premises is a standard eligible input service, unlike the specifically blocked categories in Section 17(5).

What happens if my supplier never files their return?
The invoice won’t appear in your GSTR-2B, and you generally can’t claim ITC on it until they file — even though you paid them correctly. This is why supplier compliance history matters when choosing who to buy from.

How long do I have to claim ITC on an invoice?
The deadline is the earlier of 30th November following the end of the financial year, or the date of filing the annual return (GSTR-9) for that year.

ITC is what makes GST a value-added tax rather than a cascading one, but the credit is conditional at almost every step — on your supplier’s filing, on the category of purchase, on timely payment, and on timely e-invoice reporting where it applies. Reconcile against GSTR-2B monthly, keep blocked categories out of your claims, and the reversals and notices mostly stay avoidable.