The Hidden SplitThe scheduled principal-and-interest amount may remain level in a fixed-rate example even while its internal split changes.
System guide / Housing
Mortgages & Housing
Mortgage amortization explains why a stable scheduled principal-and-interest payment can reduce the balance slowly at first. The payment has two jobs, and their shares change over time.
Key concepts
Read the mortgage payment correctly.
This is a structural guide, not personalized mortgage advice. Loan terms and servicing arrangements vary.
The borrowing cost for the balance still outstanding. In a simplified monthly schedule, it follows the remaining balance and monthly rate.
The portion that reduces what is owed. A smaller new balance changes the next payment's interest calculation.
Taxes, homeowners insurance and possible mortgage insurance can make the total sent to a servicer higher than scheduled P&I.
How amortization moves
Balance → interest → principal → new balance.
Each scheduled payment covers the interest produced by the remaining balance. The rest of scheduled P&I reduces principal, creating the balance used for the next cycle.
Early in a long fixed-rate loan, the balance is still large. That can leave a larger interest share and a smaller principal share, even though the scheduled P&I amount is stable.
- 01Start with the remaining balance
- 02Calculate the period's interest
- 03Apply the rest of scheduled P&I to principal
- 04Repeat from the new balance
Coming next / In production
Why Your Mortgage Barely Shrinks at First
The next investigation will trace the stable scheduled payment and the gradually changing split inside it. The full episode and its exact reveal are not public yet.
Same payment. Different split.Public preview only. No Case 002 page or public video is available.