 The interest rate charged on a Foreign currency mortgage is based on the interest rates applicable to the currency in which the mortgage is denominated and not the interest rates applicable to the borrower's own domestic currency.Therefore, a Foreign currency mortgage should only be considered when the interest rate on the foreign currency is significantly lower than the borrower can obtain on a mortgage taken out in his or her domestic currency.Borrowers should bear in mind that ultimately they have a liability to repay the mortgage in another currency and currency exchange rates constantly change.