10% Overpayment calculator

saajan_12

I don't think an excel or calculator would help here, as working out 10% of a number isnt' usually the hard part.. The complexity is its a different reference number for different lenders.. eg 
- 10% of starting balance
- 10% of balance at the start of the calendar year in which you're repaying
- 10% of the balance on the last anniversary of when you received your offer
- 10% of the balance on the last anniversary of when you drew down the mortgage
- 10% of current balance at the point of repayment

BikingBud

The modeller I linked should be able to cope with all of those just add the value into the "Monthly Overpayment Manual" column in the cell for the appropriate time. eg if your have 10% per year the monthly overpayment cell should be 0.1*"Start Balance" for Jan of that year. You could do that as a lump in Jan or perhaps 2 or 3 times through the year, I have added 2 overpayments of 5% first year and one of 10% in years 2 and 3:



You will need to run the different rules for different lenders but quite clearly always being able to overpay by 10% of the starting loan is start balance for the first month of the mortgage, so £20k below, whereas others you will need to accurately interpret the leeway the mortgage terms allow.





Leave Mortagage1 as the baseline and compare as required.

The first sheet above saves £85k which should foreshorten the mortgage to 17 years.

The second sheet above saves £96k which should foreshorten the mortgage to just over 16 years.