Self-assessment obligation: pay tax, interest and fees before filing return, with proof, or face default consequences.
Clause 266 requires payment, before filing the return, of any tax payable together with interest and fee and proof of such payment; payments short are appropriated in the order fee, then interest, then tax; interest is computed after reducing advance tax, TDS/TCS and specified reliefs and credits; ''assessed tax'' is defined as tax on returned income reduced by those credits and reliefs; failure to pay renders the assessee an assessee in default and triggers recovery and penal consequences without prejudice to other liabilities.