Money prizes on savings

Q: I would like to ask Your Eminence about saving and how it is estimated. A bonus of 10% is given every year, but it is not added as capital for the following year; rather it is estimated at the end of retirement. For example, if an employee receives a salary of 3000 (Part No. 13; Page No. 514) Saudi riyals, saves 600 riyals per month, and keeps working for five years, then their saving is calculated as follows: 600 × 12 = 7200 riyals; 7200 × 5 = 36000 riyals. The employee is given a bonus of 50%, that is, 36000 × 50 / 100 = 18000 riyals. This sum is added to the money the employee has been saving for five years to be as follows: 36000 + 18000 = 54000 riyals. I read the Fatwa attached to this letter in which Shaykh Ahmad Hasan Muslim, member in Al-Azhar Fatwa Committee, said: "Financial rewards for encouraging saving are permissible regardless of their type." This being the case, what is the difference between bonus and rewards? Is bonus Haram (prohibited) or Halal (lawful)? After reading this Fatwa, some Muslims thought that saving is Halal.I wish Allah, then Your Eminence would advise and guide me to the straight path. May Allah reward you the best.

A: Saving in the way you mentioned is Haram, because adding 50% to the amount of the money saved during a period of five years is considered a usurious increase. May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.