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ITC Reversal When Goods Become Exempt: Rule 42, Rule 43 & Section 18(4) Formulas

July 24, 20269 min readAkib Husain

Quick Answer: How to Calculate ITC Reversal on Exempt Supplies?

When goods become exempt, reverse common ITC monthly under Rule 42 using the formula D1 = (Exempt Sales ÷ Total Sales) × Common Credit, plus D2 = 5% for non-business use. For wholly exempt stock, reverse input credits and capital asset credits (based on a 60-month useful life) via Form ITC-03 under Section 18(4).

  • Rule 42 covers inputs and input services; Rule 43 covers common capital assets.
  • Capital goods useful life is statutorily fixed at 60 months (5 years).
  • Wholly exempt stock reversals require Form ITC-03 filing on the GST portal.
  • TallyPrime Stat Adjustment (Alt+J) posts Rule 42/43 entries directly into GSTR-3B Table 4B.

1. Rule 42 & Rule 43 Statutory Reversal Formulas

Common Credit (C2): Total ITC minus (T1: Non-business + T2: Exempt only + T3: Section 17(5) Blocked + T4: Taxable only)

Exempt Reversal (D1): (Aggregate Exempt Turnover ÷ Total State Turnover) × C2

Non-Business Reversal (D2): 5% of Common Credit (C2)

Net Monthly Reversal: Reported in Table 4B(1) of GSTR-3B return.

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Akib HusainExpert Reviewer

Founder & Chief Architect of TrulyInvoice

Last Verified: July 24, 2026
TallyPrime FY 2026-27 (v4.0+)
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