Where any tax and interest under sections 234A, 234B and 234C is payable by the assessee on the basis of the return of income required to be furnished under section 139 or section 142(1) or section 148 or section 153A, after deducting;

• The amount of tax, if any, already paid under any provision of this Act;
• Any tax deducted or collected at source;
• Any relief of tax or deduction of tax claimed under section 90 or section 91 on account of tax paid in a country outside India;
• Any relief of tax claimed under section 90A on account of tax paid in any specified territory outside India referred to in that section; and
• Any tax credit claimed to be set off in accordance with the provisions of section 115JAA,

Then the assessee shall pay such tax and interest before furnishing the return and the proof of such payment should be attached with the return of income.

In simple words, the payment required to be made under section 140A along with the return of income shall be as under:

Income tax (including surcharge, if any, and education cess) on the returned income  (A)

Add: Interest under sections 234A, 234B, 234C   (B)

Less: Relief of tax under sections 89/90/90A/91   (C)

Less: Mat credit under section 115JAA  (D)

Less: TDS/TCS   (E)

Less: Advance Tax (F)

A-B-C-D-E-F = Amount to be paid by way of self assessment under section 140A.

Notes:-

1.   Where the amount paid by the assessee under section140A is less than the amount required to be paid under section 140A, then the amount so paid shall be first adjusted towards the interest aforesaid and the balance towards the tax.

2.   If the assessee fails to pay the whole or part of tax or interest required to be paid under section 140A, then he shall be deemed to be an assessee in default in respect of the tax and interest remaining unpaid. The assessee shall have to pay interest under section 220 and penalty under section 221 for being an assessee in default. The assessee shall be deemed to be assessee in default from the next day of filing of return.