Lenders will often guarantee an interest rate to you as much as 120 days before your mortgage matures. And, as long as you are not increasing your mortgage, they will cover the costs of transferring your mortgage too. This means a rate promised well in advance of your maturity date, thus eliminating any worries of higher rates. And if rates drop before the actual maturity rate, the new lender will usually adjust your interest rate as well. Most lenders send out their mortgage renewal notices, offering existing clients their posted interest rates. The rate you are being offered is usually not the best one. Always investigate the possibility of a lower interest rate with your lender or another lender. If you don’t, you may end up paying a much higher interest rate on your renewal mortgage than you need to.