Overdraft Interest Calculator

Overdraft ("cheque especial") interest

Overdraft charges daily compound interest on whatever your balance goes negative: debt = principal · (1 + i_day)^days, where i_day = (1 + i_month)^(1/30) − 1. Between 2024 and 2026 the typical rate runs around 10-15% per month, depending on the bank and your credit score. BCB Resolution 4.765/2019 caps it at 8% per month, though banks may add a fixed annual fee once the available limit goes past R$ 500. Take R$ 500 used for 15 days at 7% per month and you're looking at roughly R$ 17 in interest.

Applications

Stack overdraft up against a CDC (3-8% per month) or a payroll-deductible loan. Look into portability between banks too, since digital banks usually price better. The thing to avoid is leaning on overdraft as a recurring credit line. Even capped at the regulated 8% per month, it compounds daily and ranks as the second most expensive line in the whole system, beaten only by revolving credit-card debt.

FAQ

What is the legal cap? BCB Resolution 4.765/2019 holds the rate to 8% per month, plus a fixed annual fee on limits above R$ 500.

Why do banks still charge 10-15% per month? The 8% cap covers the contracted rate, but some institutions bundle it with mandatory fees and insurance that drag the effective cost up. Look at the CET (Total Effective Cost) they're required by law to disclose.

How does it compare to CDC? A CDC personal loan runs 3-8% per month, so it's far cheaper. Once you're stuck in overdraft past a few days, moving the debt to a CDC almost always pays off.

Does it affect my credit score? Just using overdraft won't lower your score on its own. Staying negative for long stretches or missing payments, on the other hand, will land you on Serasa/SPC reports.