Normally, there is no definite response to the question of when you should make overpayments on your mortgage loan. It all depends on a few variables and the kind of mortgage deal that you have. That being said, if you're eager to save some money along the way then it would be much more prudent for you to pay off as much debt as possible before interest rates are reassessed or reset. Make sure that your lender has properly informed you regarding when these processes take place so that paying additional mortgage repayments can actually benefit your pocket in an effective manner. If your mortgage interest rate is assessed daily, it makes sense to make overpayments at any time. However, if the interest rate recalculates on a monthly or yearly basis, it may be wise to consider making a lump sum overpayment just before the mortgage anniversary takes place in order to take advantage of potential savings!