Key Takeaways
- An inverted duty structure arises when GST on inputs (raw materials) exceeds GST on output supplies (finished goods), causing unused ITC to accumulate
- Section 54(3)(ii) of the CGST Act allows refund of this accumulated ITC; Rule 89(5) prescribes the maximum refund formula
- Refund applies only to ITC on inputs (goods): input services and capital goods are excluded from the refund computation (Supreme Court, VKC Footsteps, September 2021)
- From 1 October 2025, low-risk refund applications receive 90% provisional refund under CGST Instruction 6/2025
- Refund must be claimed within 2 years from the end of the financial year in which the claim arises
- Supplies of edible oils (Chapter 15) and coal (Chapter 27) are excluded from IDS refund by Notification 9/2022-Central Tax (Rate)
What is an inverted duty structure in GST? An inverted duty structure (IDS) exists when the GST rate on inputs used in manufacturing or processing is higher than the GST rate charged on the finished output supply. The excess input tax credit (ITC) that accumulates because of this rate differential cannot be fully utilized against the lower output tax liability, locking up working capital unless a refund is claimed under Section 54(3) of the CGST Act, 2017.
Why Inverted Duty Structure Matters for Your Business
When you buy raw materials at 18% GST and sell finished goods at 5% GST, you pay more tax on purchases than you collect on sales. Every month, the gap widens. Your Electronic Credit Ledger swells with unusable ITC while your cash goes to suppliers and the government.
Without claiming a refund, this ITC sits idle indefinitely. For a manufacturer with Rs 50 lakh in monthly purchases taxed at 18% and Rs 60 lakh in sales taxed at 5%, the monthly ITC accumulation is roughly Rs 6 lakh (Rs 9 lakh input tax minus Rs 3 lakh output tax). Over a year, that is Rs 72 lakh locked up.
Section 54(3)(ii) of the CGST Act provides the mechanism to access this amount.
Which Industries Face Inverted Duty Structure
Inverted duty structure is most common in manufacturing sectors where raw materials attract higher GST than finished products.
Filing Frequency
You can file IDS refund for each tax period separately. Monthly filers can claim every month; quarterly filers can claim every quarter. There is no restriction on claiming for consecutive periods.
Time Limit
File within 2 years from the last date of the financial year in which the tax period falls. For the July 2026 period, the deadline is 31 March 2029. Missing this deadline means the refund claim is time-barred (though the Gujarat High Court has held in July 2025 that circulars cannot override the statutory time limit).
Documents to Keep Ready
While the portal auto-fills most data from returns, keep these records for the proper officer's verification:
- Purchase register with HSN codes showing input GST rate for each line item
- Sales register showing output GST rate and value for inverted rated supplies
- GSTR-2B reconciliation confirming ITC claimed matches supplier filings
- Stock statement (if requested) to demonstrate that inputs were consumed in manufacturing the inverted rated output
- CA certificate (if refund exceeds Rs 2 lakh per application, the proper officer may request one)
- Declaration that refund claim does not include ITC on input services or capital goods
- No unjust enrichment declaration confirming the tax burden was not passed on to buyers
Common Reasons for Refund Rejection
Knowing why IDS refund claims get rejected helps you file correctly the first time.
Mismatch between GSTR-1 and GSTR-3B: If the turnover or tax figures in GSTR-1 do not match GSTR-3B, the officer will issue a deficiency memo (Form RFD-03). Reconcile returns before filing.
Including input services in Net ITC: The most common computational error. Net ITC in the formula includes only inputs (goods). If you include service ITC, the computed refund will exceed the eligible amount and get scaled down or rejected.
ITC not reflected in GSTR-2B: ITC on inputs must be confirmed by the supplier's GSTR-1 filing. If your supplier has not filed or reported the invoice incorrectly, the ITC will not appear in your GSTR-2B, and the refund may be reduced.
Filing after the 2-year window: The statutory time limit under Section 54(1) is two years from the relevant date. Late applications are rejected.
Claiming for excluded goods: If your output falls under Chapter 15 (edible oils) or Chapter 27 (coal), IDS refund is blocked by Notification 9/2022.
IDS Refund vs Export Refund: Key Differences
Both use Form RFD-01 but the rules differ significantly.
