FBS has a shelf life of 5 years from the date of manufacture, provided it is stored appropriately. We would recommend enquiring about the shelf life of each available batch if it is important to have a long shelf life following purchase.
While there may be a drop off in growth promotion properties over time, the level of any change will depend on the cell type and assay conditions. Therefore, should a batch of serum be coming up to its original expiry date and it is still performing adequately, rather than destroy the material, APS is happy to extend the expiry date by 12 months. This re-test may be performed on a rolling 12 month basis. This means that the considerable time and investment in batch testing of a large batch of material need not be wasted should the supply last longer than forecasted.