For GSTR-3B and GSTR-1 — calculate exact late fee and interest on delayed filing.
Rates used: ₹50/day (₹25 CGST + ₹25 SGST) for regular returns, capped at ₹10,000. ₹20/day (₹10+₹10) for NIL returns, capped at ₹500. Interest at 18% p.a. on net tax liability under Section 50. This is an estimate — the GST portal's own auto-calculation at the time of filing is authoritative. For GSTR-9/9C or composition returns, rates differ — consult your CA.
Avoid late fees entirely
GSTAgent's Monthly Tracker flags pending reconciliations before deadlines — so you never file in a rush.