Dear Praveen,
Section 43B
CERTAIN DEDUCTIONS TO BE ONLY ON ACTUAL PAYMENT.
Notwithstanding anything contained in any other provision of this Act, a deduction otherwise allowable under this Act in respect of -
(a) Any sum payable by the assessee by way of tax, duty, cess or fee, by whatever name called, under any law for the time being in force,
(b) Any sum payable by the assessee as an employer by way of contribution to any provident fund or superannuation fund or gratuity fund or any other fund for the welfare of employees,
(c) Any sum referred to in clause (ii) of sub-section (1) of section 36,
(d) Any sum payable by the assessee as interest on any loan or borrowing from any public financial institution or a state financial corporation or a state industrial investment corporation, in accordance with the terms and conditions of the agreement [ 692c governing such loan or borrowing.
(e) Any sum payable by the assessee as interest on any term loan from a scheduled bank in accordance with the terms and conditions of the agreement governing such loan, shall be allowed (irrespective of the previous year in which the liability to pay such sum was incurred by the assessee according to the method of accounting regularly employed by him) only in computing the income referred to in section 28 of that previous year in which sum is actually paid by him.
Provided that nothing contained in this section shall apply in relation to any sum referred to in clause (a) or clause (c) or clause (d) or clause (e) which is actually paid by the assessee on or before the due date applicable in his case for furnishing the return of income under sub-section (1) of section 139 in respect of the previous year in which the liability to pay such sum was incurred as aforesaid and the evidence of such payment is furnished by the assessee along with such return 694a :
Provided further that no deduction shall, in respect of any sum referred to in clause (b), be allowed unless such sum has actually been paid in cash or by issue of a cheque or draft or by any other mode on or before the due date as defined in the Explanation below clause (va) of sub-section (1) of section 36 and where such payment has been made otherwise than in cash, the sum has been realised within fifteen days from the due date.
Explanation [1] : For the removal of doubts, it is hereby declared that where a deduction in respect of any sum referred to in clause (a) or clause (b) of this section is allowed in computing the income referred to in section 28 of the previous year (being a previous year relevant to the assessment year commencing on the 1st day of April, 1983 or any earlier assessment year) in which the liability to pay such sum was incurred by the assessee, the assessee shall not be entitled to any deduction under this section in respect of such sum in computing the income of the previous year in which the sum is actually paid by him.
Explanation 2 : For the purposes of clause (a), as in force at all material times, "any sum payable" means a sum for which the assessee incurred liability in the previous year even though such sum might not have been payable within that year under the relevant law.
As per Explanation 2 it is made clear that service tax liability is to be disallowed even though its payment is not due...
Hope this is enough for ur querry...
Harshal Sutaria