Late fee for delayed GST returns: daily penalty applies, with a fixed cap for supply/returns and a turnover-based cap for annual return A late fee is imposed for failure to furnish specified GST returns or supply details by the due date: failures under sections 37, 38, 39 or 45 attract a daily fee subject to a fixed maximum cap, whereas failure under section 44 attracts the same daily fee but with a maximum cap calculated as a turnover-based percentage of the registrant's State turnover.