How credit card interest works in New Zealand
Credit card interest in New Zealand can be confusing, but understanding how it's calculated is essential to managing your debt effectively. Interest is charged when you don't pay your full balance within the interest-free period, and the amount you owe grows each day until the balance is repaid.
When you use a credit card, you're borrowing money from the bank. If you pay off the full balance by the due date, you pay no interest. However, if you carry any balance forward into the next billing cycle, interest charges apply immediately.
Purchase rate vs cash advance rate
Purchase rate
The purchase rate is the interest charged on regular purchases made with your credit card. This is the rate quoted most prominently by banks. In New Zealand, purchase rates typically range from 12% to 22% p.a., depending on the card type and your creditworthiness.
Rates are often expressed as either a fixed percentage (e.g., 17.99% p.a.) or a variable rate that moves with the Reserve Bank of New Zealand's Official Cash Rate (OCR). Most consumer credit cards charge fixed rates rather than variable rates.
Cash advance rate
Cash advance rates are significantly higher than purchase rates, typically 1-2% higher. For example, if your purchase rate is 18% p.a., your cash advance rate might be 20% p.a. Additionally, most banks charge a cash advance fee of 2-3% on top of the amount withdrawn, plus ATM fees if you use a non-bank machine.
Because of these additional costs, it's best to avoid using your credit card to withdraw cash unless absolutely necessary. If you need cash urgently, a personal loan is usually cheaper.
Understanding interest-free periods
Most NZ credit cards offer an interest-free period on purchases, typically 40-55 days from the start of a billing cycle. This means you can make purchases without paying interest, provided you pay off the full balance by the end of the interest-free period.
Important points about interest-free periods:
- The interest-free period applies only to new purchases, not to existing balances or cash advances
- If you carry any balance from the previous month, interest is charged on that balance from the day the previous cycle ended
- If you make a payment but don't pay the full balance, the unpaid amount will start accumulating interest immediately
- Some cards offer longer interest-free periods (up to 55 days) as a promotional feature
Comparison of typical credit card rates by type
| Card type | Typical purchase rate (p.a.) | Cash advance rate (p.a.) | Annual fee |
|---|---|---|---|
| Low-rate | 12-16% | 14-18% | $50-$100 |
| Standard | 18-21% | 20-23% | $0-$75 |
| Rewards/cashback | 18-21% | 20-23% | $0-$150 |
| Airpoints | 16-20% | 18-22% | $150-$350 |
How interest is calculated
Credit card interest is typically calculated on a daily balance basis. This means interest is charged based on your balance at the end of each day, not your average balance over the month. If you pay down your balance partway through the month, the daily interest charge decreases proportionally.
Here's how a typical calculation works:
- Your balance: $2,000
- Interest rate: 18% p.a. (0.0493% per day)
- Daily interest charge: $2,000 × 0.000493 = $0.99
- If you maintain this balance for 30 days: $0.99 × 30 = $29.70
This demonstrates why even small balances can grow quickly if left unpaid.
How to avoid paying credit card interest
Pay your full balance each month
The most straightforward way to avoid interest is to pay your entire balance by the due date each month. This requires disciplined spending and budgeting, but it's the most cost-effective way to use a credit card.
Use the interest-free period strategically
If you know you'll need to carry a small balance for a short time, make your large purchase early in the billing cycle. This gives you the full interest-free period (up to 55 days) before interest starts accruing.
Set up automatic payments
Set up an automatic payment to transfer your full credit card balance to your card each month. Many banks offer this feature for free, and it helps ensure you never miss a payment or accidentally carry an unwanted balance.
Avoid cash advances
Cash advances charge higher interest rates and additional fees, making them one of the most expensive ways to borrow. If you need cash, withdraw from your bank account or consider a personal loan instead.
Pay down existing balances strategically
If you're already carrying a balance, prioritise paying off the highest-interest debt first. This might be your credit card rather than a lower-interest personal loan, so focus your extra payments on your credit card balance.
Pro tip: Track your billing cycle
Write down your billing cycle dates and due date. Making a payment just after the due date means you'll start the new cycle with a $0 balance, maximising your interest-free period on new purchases.
Frequently asked questions
Can I get a lower interest rate on my credit card?
Yes, rates vary significantly by bank and card type. To get a lower rate, ensure your credit score is strong (above 700 is typically considered good). You can also apply for a low-rate card with a different bank, though this triggers a hard credit inquiry. Banks sometimes offer promotional rate reductions if you call to request one.
What happens if I only pay the minimum amount?
If you only pay the minimum (usually 2-3% of your balance), the rest of your balance will accumulate interest. On a $5,000 balance at 18% p.a., paying only the minimum means you could take 5-6 years to repay and pay over $2,000 in interest.
Is 20% interest rate high for a credit card in NZ?
No, 20% is typical for a standard NZ credit card. Low-rate cards start at around 12%, while some cards charge 22% or more. However, any credit card interest is high compared to other borrowing options like personal loans (8-15% p.a.) or mortgages (5-8% p.a.).
Do banks ever charge compound interest on credit cards?
No, credit card interest is calculated as simple interest, not compound interest. Interest is charged daily based on your balance, but it's not compounded on top of previously accrued interest.
Why is my cash advance rate so much higher than my purchase rate?
Cash advances are considered riskier than purchases because they represent immediate lending without the purchase of goods or services. Banks charge higher rates and fees to cover this increased risk. Additionally, interest on cash advances begins immediately with no interest-free period.