Late fee waiver for delayed GSTR-3B filings provides conditional relief for specified taxpayers and tax periods, subject to thresholds. Rationalises the waiver of late fee for delayed filing of FORM GSTR-3B by substituting a table of class-based waiver periods effective 20 May 2021, providing a conditional retrospective waiver for July 2017-April 2021 if returns are filed between 1 June and 31 August 2021 (with a lower ceiling where state tax is nil), and prescribing nominal excess-waiver amounts for late filings from June 2021 onwards according to taxpayer class and tax profile.