In comparison to other types of mortgages, when the interest rates are low, the borrowers monthly repayments might be less. However, this also means that when the interest rates are higher, so are the monthly repayments. Alike with a SVR mortgage, the borrower can never be certain of what their monthly repayment amount will be. Although the interest rate on a tracker mortgage is based to BoE interest rate, the actual interest rate applied on the mortgage will be determined by the lender. This is quite often higher than the base rate. Most tracker mortgages run between one and five years, but some may run until the end of the mortgage term. On completion of the tracker mortgage, most lenders will switch the mortgage to a standard variable rate of interest.