How the French Amortization System Works
The French amortization system is the most common method for mortgage repayment worldwide. It features fixed monthly payments throughout the loan term, making budgeting predictable.
Each payment consists of two parts:
- Principal - Reduces your loan balance
- Interest - Cost of borrowing, calculated on remaining balance
Key Insight
Early in your loan, most of your payment goes to interest. Over time, more goes to principal. This is why early extra payments have the biggest impact on total interest.
Understanding Your Monthly Payment
Your payment depends on three factors:
- Loan Amount - Total amount borrowed
- Interest Rate - Annual cost of borrowing
- Loan Term - Repayment period (typically 15-30 years)
The Formula
M = P × [r(1+r)n] / [(1+r)n - 1]
Where M = monthly payment, P = principal, r = monthly rate, n = total payments.
Rate Shopping Tip
A 1% rate difference can mean $65,000+ in interest over 30 years on a $300k loan. Always compare at least 3-4 lenders.
Strategies to Pay Off Faster
Making extra payments is one of the most effective ways to save money:
Extra Monthly Payments
Even $100-200 extra per month can save years and tens of thousands in interest. The extra amount goes directly to principal.
Bi-Weekly Payments
Pay half your monthly payment every two weeks. This results in 26 half-payments (13 full payments) per year instead of 12, effectively making one extra payment annually.
Lump Sum Payments
Tax refunds, bonuses, or inheritances can be applied directly to principal for significant interest savings.
Check for Prepayment Penalties
Some mortgages charge fees for early repayment. Review your loan terms first. Most modern mortgages don't have these penalties.
Mortgage Affordability Guidelines
The 28/36 Rule
Lenders typically use the 28/36 rule:
- 28% - Maximum of gross income for housing costs (mortgage, taxes, insurance)
- 36% - Maximum of gross income for all debts combined
Down Payment Considerations
A 20% down payment avoids PMI (Private Mortgage Insurance), which typically costs 0.5-1% of the loan annually. However, smaller down payments (3-10%) may be appropriate if you need to maintain emergency savings.
Fixed vs Variable Rate Mortgages
Fixed-Rate
- Same rate for entire loan term
- Predictable payments
- Protection against rate increases
Variable (Adjustable) Rate
- Rate changes with market conditions
- Often starts lower than fixed
- Good if planning to sell/refinance before adjustment
Frequently Asked Questions
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