Interest relief for delayed GST returns provides phased nil and reduced rates, with late fee waiver conditional on notified filing dates. Reduced rates of interest and conditional waiver of late fee apply to delayed GST returns for specified tax periods. For larger taxpayers a nil-interest initial window is followed by a reduced interest rate, reverting to the normal rate after the prescribed period; the circular provides illustrative day-wise calculations for GSTR-3B filings. For smaller taxpayers a nil-interest period until specified dates is followed by a reduced rate until a later cutoff, after which the standard rate applies. Waiver of late fee is conditional on filing by notified dates; otherwise late fee accrues from the original due date.