Credit Card Repayment Calculator

How the Credit Card Repayment Calculator Works

Credit card interest in South Africa is calculated daily on the closing balance and charged to your account at the end of each statement cycle. This is different from a personal loan, where interest is calculated on the outstanding balance each month using the simple interest annuity method.

The daily interest rate is derived by dividing the annual rate by 365. If your card carries a balance of R10 000 at 20% per year, the daily interest charge is approximately R5.48 - compounding every day the balance remains outstanding.

The calculator models monthly cycles: it deducts your monthly payment from the balance, adds one month's interest, and repeats until the balance reaches zero. It shows you:

• Number of months to pay off the balance
• Total interest paid over that period
• Total amount paid (principal + interest)
• A comparison between minimum repayment and a chosen fixed payment

South African credit cards typically set the minimum repayment at the higher of R25 or 2–3% of the outstanding balance. Paying only the minimum on a R20 000 balance at 20% per year can take over 10 years and cost more than R12 000 in interest - the calculator makes this stark reality visible.

How to Use This Calculator

1. 1

   Enter your current balance

   Use the outstanding balance on your latest credit card statement - not the credit limit. If you carry balances on multiple cards, run a separate calculation for each one.

2. 2

   Enter your annual interest rate

   This appears on your monthly statement as the 'purchase rate'. South African credit cards are capped by the NCA at the repo rate plus 14% for credit facilities - currently 22.25% maximum. Rates vary by card and credit profile.

3. 3

   Choose your repayment method

   Select 'Minimum repayment' to see the worst-case scenario, or enter a fixed monthly amount to see how much faster and cheaper you can clear the debt. Try increasing the payment by R200–R500 to see the dramatic impact on payoff time and interest.

4. 4

   Review the payoff timeline

   The results show the number of months and the payoff date alongside total interest. Use this to set a concrete goal - for example, paying off by a specific month by committing to a fixed payment.

5. 5

   Compare scenarios

   Run the calculation twice - once at minimum repayment, once at a higher fixed amount - and compare the interest saved. The difference is often thousands of Rands for balances above R10 000.

Frequently Asked Questions

What is the maximum credit card interest rate in South Africa?

Under the National Credit Act, credit card and revolving credit interest is capped at the South African Reserve Bank repo rate plus 14% per year. With the repo rate at 8.25% (mid-2025), the maximum is 22.25% per annum. In practice, standard credit card rates from major South African banks range between 18% and 22.25%, depending on your credit score and income.

How is the minimum repayment calculated on South African credit cards?

Each bank sets its own minimum, but the NCA requires it to cover at least the monthly interest charge plus a small portion of principal - preventing indefinite interest-only payments. Most South African banks set the minimum at the greater of R25 or 2% to 3% of the outstanding balance. This means if you owe R15 000, your minimum could be as low as R300 - while monthly interest alone is over R250, meaning you'd barely reduce the principal.

Does paying only the minimum affect my credit score?

Paying the minimum on time does not in itself damage your credit score - you are meeting the contractual obligation. However, consistently paying only the minimum signals to credit bureaux that you are financially stretched, and your high credit utilisation (balance versus limit) negatively impacts your score. Paying down the balance improves your utilisation ratio and score.

What happens if I miss a credit card payment in South Africa?

Missing a minimum payment typically triggers a late payment fee (usually R100–R200) and a negative mark on your credit record at the credit bureaux. After 30 days, lenders report the account as 'overdue'. After 90 days, it can be classified as 'defaulted', which severely damages your credit score and may result in the bank handing the account to a collections agency. One missed payment can affect your ability to get credit for up to five years.

Is it better to pay off my credit card or invest the extra money?

If your credit card charges 20% interest and your investment earns 10–12% (typical for a South African equity fund over the long term), paying off the card first is mathematically better - a guaranteed 20% return versus a probable 10–12%. The exception is if your employer offers a matched retirement contribution: the match doubles the effective return of investing, which can outweigh the credit card saving.

Can I negotiate a lower credit card rate with my bank?

Yes. If you have a good payment history and a strong credit score, South African banks will often negotiate the interest rate on request. Call the retentions team rather than the general credit card line. You can also apply for a balance transfer to a card with a lower rate or an interest-free promotional period - some banks offer 0% on transferred balances for 6 months.