Reversal under Rule 37 — failure to pay supplier within 180 days — the recipient must:

1. Rule 37 (substituted w.e.f. 01.10.2022) — if value + tax not paid within 180 days, the recipient must pay an amount equal to the ITC availed. 2. This is to be furnished in Form GSTR-3B for the tax period immediately following the expiry of the 180-day window. 3. Interest applies at the Sec 50 rate (18% p.a.). On subsequent payment to supplier, ITC can be re-availed (no time bar). _Source: ICAI BoS CA Final Paper 8, Ch 6 "Input Tax Credit", §Rule 37_