Whatâs the standard for calculating mortgage interest payments in Switzerland?
Weâve just made our first ever quarterly mortgage interest payment. I was trying to calculate exactly how much it would be, and ended up being wrong, though not far off. Got me rereading the loan documents and found that the interest for our SARON mortgage is calculated using the âactual days / 360â method.
Basically the interest rate is divided by 360, then multiplied by the actual number of days in that quarter (92 for Q3), then multiplied to the mortgage. So for example, the Q3 payment for a mortgage of CHF 1 million with a 0.55% rate (SQ) would be CHF 1,405.56
Contrast that with how I assumed it was calculated (this is the predominant method in my country of origin), which is the âactual days / 365 or 366â method. Same steps as above but dividing by 365 instead - the payment for Q3 with the same parameters would be CHF 1,386.30
Tiny difference, yes, but 19.26 per quarter, turns into 77.03 per year, then before you know it, youâve paid an âextraâ CHF 1,155 over 15 years just because somebody decided it would be a great idea to define a âyearâ as 360 days instead of 365/6!!!
Setting aside the problematic morality of this practice, for those who have a SARON mortgage, what method does your lender use? And just out of curiosity, is this something that can be negotiated out of, or specified during a mortgage renewal?
I know itâs incredibly dull and a bit pedantic, but I have the time, and apparently so do you, if youâve read this far 