Presumptive taxation of non-resident shipping income uses gross freight receipts and a pre-departure return mechanism. Special presumptive regime applies to non-residents operating ships, other than cruise ships, for computing profits and gains from shipping operations. Income from carriage of passengers, livestock, mail or goods shipped at an Indian port, and corresponding receipts from carriage at ports outside India that are received or deemed received in India, is deemed at 7.5% of the relevant gross receipts, including demurrage, handling and similar charges. The general computation provisions are overridden to the extent inconsistent with this special rule, and no loss, allowance or deduction is permitted against the deemed income. The regime also provides a collection and assessment mechanism. The master of the ship must furnish a return before departure, subject to relaxation where immediate filing is not possible and a substitute filing arrangement is made. The Assessing Officer then assesses the deemed income, determines tax, and port clearance is withheld unless tax is paid or satisfactory arrangements are made. The owner or charterer may instead seek regular assessment, and amounts paid are treated as advance tax.