(1) (a) A registered dealer entitled to refund in pursuance of any order under this Act including an order of assessment under sections 40, 42, 42A and 43 or in pursuance of any order of a Court shall, in addition to the refund, be paid in the prescribed manner simple interest at the rate of eight per centum per annum for the period commencing immediately after the expiry of sixty days of receipt of the order till the date on which therefund is granted:

Provided that interest as applicable under this section shall be admissible after the expiry of the period of ninety days from the date of receipt of the application for grant of refund under sub-section (1) of section 58 till the date of its sanction.

(b) The interest payable under clause (a) shall be calculated on the amount of refund as due after deducting therefrom any tax, interest, penalty or any other dues payable by the dealer under this Act.

(c) If, as a result of any order passed under this Act, the amount of such refund is enhanced or reduced, such interest shall be enhanced or reduced accordingly, and where the interest is reduced, the excess amount of interest granted, if any ,shall be recovered as if it is an arrear of tax under this Act.

(2) Where, as a result of any final order, the amount of tax including penalty,if any, is -

(a) found to be not due or not defaulted, the interest paid, if any, on that account shall be refunded; or

(b) reduced, the interest payable on that account shall be calculated accordingly and the excess amount of interest paid, if any, shall be refunded :

Provided that where any amount of tax payable is enhanced by any such final order, interest shall be payable on the amount by which the tax is enhanced after the expiry of a period of three months from the date of the order :

Provided further that where the realisation of any amount remains stayed by the order of any Court or authority competent under this Act and such order is subsequently vacated, interest shall be payable also for any period during which such order remained in operation.

(3) If, as a result of an appeal or revision, any change becomes necessary in the assessment order, and the appellate authority or the revisional authority directs the assessing authority to amend the assessment order accordingly and, thereupon, the amount paid in excess, if any, shall be refunded to him without interest.