Loan repayment schedule explained
Last updated: 2026-08-14
A monthly payment tells you what leaves your account. A repayment schedule tells you what it is doing. Those are different questions, and only the second one lets you judge whether a loan is a good one.
What each row contains
Every period shows the same six figures, and they always resolve the same way:
Interest is always taken first. Principal only ever gets what is left over. That single ordering explains every counter-intuitive thing loans do — why early payments barely move the balance, why extra money is so effective, and why a payment below the interest charge never clears anything.
What the schedule reveals that the payment hides
Two loans with the same payment can cost very different amounts. A lower rate over a longer term can produce an identical monthly figure and thousands more in total interest. The payment column looks the same; the interest column does not.
The balance at any date. If you might sell or refinance in five years, the row at month 60 is the number that matters — not the payment, and not the total interest over a full term you will never reach.
When the split flips. On long loans the point where principal exceeds interest arrives far later than expected. On a 30-year mortgage it is around year 19.
Where extra payments land
Extra principal is applied after the interest due has been taken, so all of it reduces the balance. Because next period's interest is charged on that smaller balance, slightly more of the ordinary payment reaches principal too. The effect compounds forward.
This is also why timing dominates. An extra payment in month 6 has the whole remaining term to prevent interest across. The same amount near the end has almost nothing left to prevent.
Three checks worth running
- Interest in the first year. Multiply by how long you realistically expect to hold the loan. That is the cost you will actually incur.
- Balance at your likely exit. Compare it against what the asset might be worth then, particularly on vehicles.
- Total of payments versus amount borrowed. The difference is the price of the money, stated plainly.
Generate a schedule
The loan repayment calculator produces a period-by-period schedule with optional recurring and one-time extra payments. For a mortgage specifically, the amortization calculator adds the balance chart, and the loan comparison calculator runs two schedules against each other.
Related reading: mortgage amortization explained.
What changes the schedule
The same principal produces very different schedules depending on rate and term. The monthly payment and the total interest move in opposite directions as the term extends.
| Term | At 7%: payment | At 7%: total interest | At 12%: payment | At 12%: total interest |
|---|---|---|---|---|
| 24 months | $895 | $1,487 | $941 | $2,589 |
| 36 months | $618 | $2,238 | $664 | $3,918 |
| 48 months | $479 | $3,004 | $527 | $5,288 |
| 60 months | $396 | $3,785 | $445 | $6,693 |
Stretching from two years to five roughly halves the payment and more than doubles the interest. Neither column is the right answer on its own; the question is which one your budget can actually carry.
Common questions
Why is my payment the same every month?
Amortising loans are designed that way. The rate applies to a falling balance, so the interest portion shrinks and the principal portion grows, while the total stays level.
What happens if I pay early?
Less interest accrues before the next payment, so more of that payment reaches principal. Paying a few days early each month produces a small but real saving over a long term.
Can I see how much interest is left?
Yes. Total remaining interest is the sum of the interest column from today to payoff, which the schedule makes explicit. It is usually a larger number than people expect at the midpoint.
Does the schedule change if rates change?
Only on a variable-rate loan. On a fixed-rate loan the schedule is fixed at origination and moves only if you overpay or restructure.
Related reading
The rest of this series, and the calculators that let you run the idea on your own numbers.
More loan guides
Try it with your figures
See also all guides, every calculator, and the calculation methodology behind these estimates.