Hi,
Please refer Section 7(3A) in The Payment of Gratuity Act, 1972
(3A) If the amount of gratuity payable under sub-section (3) is not paid by the employer within the period specified in sub-section (3), the employer shall pay, from the date on which the gratuity becomes payable to the date on which it is paid, simple interest at such rate, not exceeding the rate notified by the Central Government from time to time for repayment of long-term deposits, as that Government may, by notification specify: Provided that no such interest shall be payable if the delay in the payment is due to the fault of the employee and the employer has obtained permission in writing from the controlling authority for the delayed payment on this ground.
As per the Payment of Gratuity Act, 1972, the rate of interest for delayed payment of gratuity is determined by the government and is subject to change from time to time. The current rate of interest for delayed gratuity payment is 8% per annum.