Mortgage debt schedule
Constant payment, interest, principal, balloon.
By Surojit Chakraverti, founder of L3VLUP and an investor running a long-short healthcare and technology equities strategy.
On this subject: mortgage debt schedule.Updated 30 September 2026
What it does
A constant-payment mortgage over the hold. The annual payment is the loan times the mortgage constant; interest is charged on the opening balance; principal is the payment less interest, so it rises each year as interest falls; and whatever is outstanding at sale is repaid as a balloon from the proceeds. DSCR is read each year against NOI.
Where it lives
The same schedule in each model that carries it, with the rows to open. Open a model in the browser, go to the sheet, and click the lines.
- Debt, rows 18–25: Opening balance, Interest, Scheduled principal, Balloon repaid at sale…
What a reviewer looks for
- Interest on the closing balance.
- A balloon forgotten at sale, so the levered return counts the lender’s money.
- A payment recomputed each year rather than fixed at origination.
Learn it, then build it
Vocabulary: DSCR (Debt Service Coverage Ratio).