How come I have been paying my mortgage for 2 years, but the balance is (practically) unchanged?

The reasons for that can be:
i) If your have a conventional fixed-rate or adjustable rate mortgage, and it is really as young as 2 years, it is natural for the balance to reduce insignificantly because of the “leveling” of monthly payments. You can find a more detailed explanation in my article about FRMs; but in short, in early years each monthly payment pays mostly towards the interest. Only in later years the monthly proportion of money paid towards the principal increases and then the reduction of the outstanding balance becomes more noticeable. The principal payment is always a remainder - the total monthly payment minus the interest; and if with a FRM everything is pre-calculated and the monthly amount is set, ARM monthly payments change to meet the new rate and serve, first of all, the interest; the principal gets the residual. Generally, this case presents nothing to worry about.
ii) If the balance is totally unchanged, you probably have an interest-only mortgage, i.e. everything you pay every month is paid towards the interest only.The balance will start to reduce only if you make an extra payment or when the interest-only period is over. For more details on Interest-Only mortgages read here.



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