Abstract This research aims to use new functions such as (general trend function – Gompertz function - function Gompertz weighted by a factor of healthy improvement) in estimating the cost of pension cost, taking into account the healthy improvement. This work is to achieve the fairness between rights and liabilities of insurance contract parties. And to obtain more accurate results for the estimates may be needed. Data experience of insurance companies through (1997-2009) has been treated to obtain the value of PX,t as estimated values, a Commutation table has been prepared and used to calculate the cost of retirement payments. Three methods have been applied to achieve that goal. A comparison has been met to show more clearance.