GST refund on inverted-duty structure — Rule 89(5) formula explained

What is "inverted duty structure"

A scenario where the rate of tax on inputs (raw materials, services) is higher than the rate on output supplies. Common examples:

• Textile manufacturers buying 18% yarn, selling 5% fabric
• Fertilizer producers buying 18% chemicals, selling 5% fertilizer
• EV battery manufacturers — input 18% / output 5%
• Some pharma intermediates — input 18% / output 12%

The result: output GST collected is less than input GST paid. ITC accumulates in the electronic credit ledger. Without refund, this is permanent locked capital.

Eligibility — only input goods (post FA 2022)

The big change: FA 2022 (effective 18-July-2022) restricted the inverted-duty refund to input goods only. Refund is no longer allowed on:

• Input services (rent, professional fees, audit fees, etc.) accumulating in the credit ledger
• Capital goods ITC

So while you may have built up ₹30 L of ITC overall, only the goods-portion is eligible for refund. Services and capital-goods ITC continue to sit until they can be utilised against future output.

The Rule 89(5) formula

Maximum refund = (Turnover of inverted-rated supply × Net ITC ÷ Adjusted total turnover) − tax payable on inverted-rated supply

Breakdown:

• Turnover of inverted-rated supply: Value of outward supplies at lower rate during the refund period (a specific month or set of months)
• Net ITC: ITC availed on input goods only (post FA 2022) during the refund period, minus any reversal
• Adjusted total turnover: All taxable + zero-rated + non-zero-rated outward turnover (excludes exempt and value of inward RCM)
• Tax payable on inverted-rated supply: The output tax on that turnover

Worked example

A textile manufacturer for the month of April 2026:

Item	Value
Outward supply of fabric (5% GST)	₹50,00,000
Output GST collected (5%)	₹2,50,000
Input goods (yarn etc.) purchased	₹30,00,000
Input GST paid (18%)	₹5,40,000
Input services (rent, freight)	₹4,00,000 + ₹72,000 GST

Maximum refund = (₹50,00,000 × ₹5,40,000 ÷ ₹50,00,000) − ₹2,50,000 = ₹5,40,000 − ₹2,50,000 = ₹2,90,000

Note: ₹72,000 of input-services ITC is not refundable. It stays in credit ledger.

The filing — Form RFD-01

Refund application is filed via Form RFD-01 on the GST portal:

1. Select category: "Refund of accumulated ITC on account of inverted duty structure"
2. Pick the refund period (one calendar month, or up to 2 years' aggregate)
3. Auto-populates Net ITC, turnovers from GSTR-3B and GSTR-1 of the period
4. Upload supporting documents: statement of invoices, undertaking, CA certificate (if refund > ₹2 lakh)
5. Submit + e-sign with DSC / EVC

2-year window: refund must be filed within 2 years from the end of the FY in which the right to refund arose.

Processing — 60-day target, often longer

Statutory processing target is 60 days from filing. Reality: average is 90-120 days, with delays often longer. The proper officer reviews documents, may issue deficiency memos (RFD-03) asking for clarifications.

If refund delayed beyond 60 days, you're entitled to interest at 6% p.a. from day 61. The interest is automatic on the order but rarely paid voluntarily — often requires follow-up.

Common rejection reasons

1. Net ITC calculation wrong — claimant included services / capital goods (no longer refundable)
2. Turnover mismatch with GSTR-1 / 3B
3. Missing CA certificate for refund > ₹2 lakh
4. Application filed beyond 2-year window
5. Inputs reported in wrong period (input-tax-credit availed in a different month than refund period)

The Finclar take

Inverted-duty refunds are real cash on the table for manufacturers in the 5%-output / 18%-input categories. We've helped clients recover ₹40 L - ₹2 Cr+ over staged filings. The discipline is in the documentation — Net ITC calc must exclude services/capital goods, turnover must reconcile to GSTR-1 / 3B, and the CA certificate (required > ₹2 L) must be unimpeachable. File monthly if cash flow matters; file quarterly if administrative effort is the constraint. Don't let unutilised ITC sit beyond a year — the 2-year filing clock is unforgiving.