Reduce Debt - How to model over-payments on a mortgage

When thinking about over-payments on a mortgage, this could be a strictly one-time over-payment, or could be an ongoing over-payment. In the first instance, there would be a temporary increase to the mortgage payment, followed immediately by a decrease, or reversion to the regular mortgage payment; in the latter instance, the over-payment could continue, potentially, until the mortgage is repaid in full.

The essential logic is the same in either case, with the only difference being that the one-time operation requires both a 'step-up', and a subsequent 'step-down' (thereby requiring two events on the timeline), whereas the latter requires (potentially) only a 'step-up' (thereby needing only a single event on the timeline); if the over-payment is ongoing, therefore, please ignore any steps that refer to a presumption of the 'regular payment'.

To model a large, one-off partial repayment of a mortgage (not a debt payoff, which is even easier to do):

1. You can add an event (if necessary) either by going to the Time screen or from within any of the data entry screens, where you would select the Time panel > Event tab and then click the New Event button.

2. Drag and drop an event onto the timeline in the year the over-payment is to occur. Name it "Mortgage Paydown", for example.

3. Place a second event in the following year of the plan. Name it "Resume Regular Mortgage Payment", for example.

4. Go to the Debt screen.

5. Select the relevant mortgage entry/item in the ledger.

6. Next, expand the Step Up / Step Down panel in the Advanced Settings.

7. Select the first of the two events to schedule the over-payment. Enter the stepped-up payment amount. Inflation rate can be left as is. Enter the full increased debt payment amount. 

Another set of fields will display automatically on the Step Up / Step Down panel allowing you to enter an additional step, e.g. to model any subsequent reduction, or reversion to the 'regular' payment amount.

8. Select the second of the two events and enter the regular mortgage payment amount, stepping it down to the usual amount in the year following the over-payment.


9. Click Update to save these changes.

Check the details of the Let's See chart to verify that this is being modelled as expected.