Updated August 31, 2026
In this guide
Two goals
An extra amortization reduces balance by the same amount in both cases. The following flow differs:
- reduce term: keeps the payment logic and removes final months;
- reduce payment: keeps the term and spreads the lower balance over remaining months.
new balance = prior balance − contribution
BRL 20,000 in month 60
BCB reference rate for fixed-rate real-estate financing: 2026-07, median of 3 institutions.
Parameters used
- Financed amount
- R$300,000.00
- Term
- 360 months
- Interest rate
- 14.9797% effective per year
- System
- SAC
- Monthly adjustment
- —
- Extra amortization
- R$20,000.00
Calculated results
| Scenario | Reduce term | Reduce payment |
|---|---|---|
| First payment | R$4,343.33 | R$4,343.33 |
| Last payment | R$1,086.76 | R$774.83 |
| Total interest | R$482,624.53 | R$598,336.89 |
| Total paid | R$782,624.53 | R$898,336.89 |
| Effective term | 274 months | 360 months |
| Accumulated adjustment | R$0.00 | R$0.00 |
Selected installments
| Payment no. | Payment | Interest | Amortization | Closing balance |
|---|---|---|---|---|
| 1 | R$4,343.33 | R$3,510.00 | R$833.33 | R$299,166.67 |
| 12 | R$4,236.08 | R$3,402.75 | R$833.33 | R$290,000.04 |
| 60 | R$23,768.08 | R$2,934.75 | R$20,833.33 | R$230,000.20 |
| 180 | R$2,269.37 | R$1,194.60 | R$1,074.77 | R$101,027.80 |
| 274 | R$1,086.76 | R$12.57 | R$1,074.19 | R$0.00 |
What changes
Reducing term often removes more interest-bearing periods; reducing payment frees more monthly cash. Interest saved and months removed are scenario outputs, not universal rules.
Check the statement to confirm that the contribution reached principal and which reference date was used.
What may differ in a contract
- The contract defines processing dates, minimum values and how the payment or term is recalculated.
- Past-due charges may be settled before the remainder reduces principal.
Limits of this analysis
- The comparison assumes the whole amount reaches principal in month 60.
- It excludes fees, penalties, operational limits and FGTS eligibility.
Sources and review
- Central Bank of Brazil — Citizen Calculator · July 27, 2026