Understanding Interest Rates and Fees on Credit Cards

Understanding Interest Rates and Fees on Credit Cards

The interest rate on a credit card is the most expensive borrowing most of us will ever use. It's higher than a personal loan, higher than a mortgage, higher than an overdraft. Standard rewards cards in New Zealand typically sit in the 19.95% to 22.49% p.a. range, and the low-rate cards that undercut them still land around 11.95% to 13.99% p.a.

Here's the part that surprises people: the interest-free period isn't a grace period on your whole balance. It runs backwards from your statement date, and it's all or nothing. Pay the closing balance in full by the due date and you pay nothing. Pay every cent except one, and interest applies from the date of each transaction.

We've pulled the actual numbers from the providers' own pages so you can see what each card really costs — the rate, the fee, and the small print that decides which of those two matters more for you.

How We Researched This Guide

We went straight to the providers. TSB's own credit card page gave us the Low Rate Mastercard at 11.95% p.a. with a $20 annual fee, and the Platinum at 20.95% p.a. with a $90 fee. SBS Bank's Visa Credit Card Fees and Charges document, dated 17 March 2026, showed a $0 annual fee against a 19.65% purchase rate. ANZ, Westpac and Air New Zealand's own card comparison page filled in the Airpoints side of the market.

The most useful find was the Gem Visa Changes FAQ dated 11 February 2026. Gem's six months interest free is no longer automatic — you have to select the eligible purchase in the Latitude App within 30 days or you lose it entirely. We also checked the lending rules set out in full on legislation.govt.nz, because the Credit Contracts and Consumer Finance Act 2003 governs what lenders must disclose before you sign.

The Quick Summary (60-Second Version)

If you only read one part of this guide, make it this.

• Standard rewards cards charge roughly 19.95% to 22.49% p.a.; low-rate cards sit around 11.95% to 13.99% p.a.
• Interest-free days run 44 to 55 days on purchases, but only if you clear the full statement balance by the due date.
• Cash advances are the trap: no interest-free period at all, and rates around 22% to 25% p.a. plus a flat fee per withdrawal.
• NZ issuers calculate interest daily — annual rate divided by 365 — on the outstanding balance, so paying early genuinely saves money.
• Annual fees range from $0 (SBS Visa, American Express Airpoints) to $150 (ANZ Airpoints Visa Platinum).
• A balance transfer's promotional rate usually covers only the transferred balance; new purchases sit at the standard rate from day one.

How the Interest-Free Period Actually Works

Your statement shows a closing balance and a due date, usually about three weeks later. Pay that closing balance in full by the due date and no interest is charged on any purchase on that statement. The interest-free window is typically 44 to 55 days depending on the card and when in the cycle you spent.

Miss it by a dollar and the whole thing collapses. Interest is calculated from the date of each transaction, not from the due date. A purchase you made 50 days ago starts accruing interest as though it had never been interest free. This catches people who think paying most of the balance is good enough.

Why daily calculation matters

New Zealand issuers work out interest daily: the annual rate divided by 365, applied to the outstanding balance each day, then added up at the end of the cycle. That has a practical upside. Pay a large purchase off mid-cycle rather than waiting for the statement date and you cut the number of days interest accrues. The earlier the payment lands, the less it costs.

The Different Rates on One Card

A single card carries several rates, and they don't behave the same way. The purchase rate covers everyday spending. The cash advance rate is higher — roughly 22% to 25% p.a. across the market — and applies to ATM withdrawals, gambling transactions and some money transfers. Cash advances have no interest-free period whatsoever. Interest starts the moment the transaction posts, even if you clear your card in full every month.

Gem Visa illustrates how far apart these can sit. The prevailing purchase rate after any interest-free term ends is 29.49% p.a., while cash advances run at 29.95% p.a. plus a $2 fee. Q Card's standard rate is 28.95% p.a., with cash advances at 29.50% p.a. These are the expensive end of the market, and they're the cards most often used for exactly the purchases people can't clear quickly.

Fees you'll actually pay

Annual fees range from nothing to $150. SBS charges $0 on its Visa Credit Card and $0 for an additional card. American Express's Airpoints Card is the only no-annual-fee Airpoints card on Air New Zealand's comparison page. At the other end, ANZ's Airpoints Visa Platinum costs $150 p.a., charged $75 half-yearly, and Gem Visa adds a $55 one-off establishment fee on top of its $65 annual fee.

Balance Transfers and the Interest-Free Catch

A balance transfer moves an existing card balance onto a new card, usually at a low or 0% promotional rate for a set period. It can be a genuinely useful tool for clearing debt. It also has a structure that works against you if you keep spending on the new card.

The promotional rate normally applies only to the transferred balance. New purchases sit at the standard rate from day one. Payments are typically applied to the lowest-rate balance first, so the transfer balance is the last thing to shrink.

Gem Visa's 30-day rule

Gem Visa used to hand you six months interest free on general purchases of $250 or more automatically. From 11 February 2026 you have to select the eligible purchase in the Latitude App or Service Centre within 30 days of it being posted. Miss that window and the transaction can no longer be selected — you lose the interest-free term completely. Foreign remittances are no longer eligible for selection at all.

Gem's own terms carry a warning worth repeating: paying only the minimum monthly repayment is not enough to clear the purchase within the promotional period. The minimum is 3% of the outstanding monthly balance or $20, whichever is more. Q Card works similarly — 3% of the monthly closing balance or $10, whichever is greater, required throughout any interest free period.

Choosing Between a Card and a Personal Loan

A personal loan is a fixed sum repaid over a fixed term at a fixed rate. A credit card is a revolving limit with no end date. If you're carrying debt you can't clear in a few months, the loan usually costs less per dollar borrowed. ASB charges a single fixed rate of 13.90% p.a. on amounts over $2,000, with no processing fee and no early repayment charge.

The fee-versus-rate trade-off

A low annual fee with a high rate suits someone who clears the balance monthly — they never pay interest, so the rate is irrelevant. A moderate fee with a low rate suits someone carrying a balance, because the interest saving can easily exceed the fee. A premium card with travel insurance suits someone who'd buy that cover separately anyway.

ANZ's Airpoints Visa Platinum charges a 0% foreign currency conversion fee and includes overseas travel insurance and personal baggage cover up to $30,000. If you travel and would otherwise buy that cover, the $150 annual fee is doing real work. If you don't travel, it isn't.

Questions You Might Have

Does checking my credit file hurt my score?

No. You can request your own credit report from any of the three New Zealand agencies — Equifax, Centrix and illion — and it won't affect your file. Lenders look at repayment history, defaults, credit enquiries, the number of active accounts and how long you've had credit.

Will a balance transfer hurt my credit score?

Applying for a new card creates a credit enquiry, which can nudge your score down slightly. Moving a maxed-out card onto a new limit lowers your overall utilisation, which lenders like.

Can a lender refuse me even with a good credit score?

Yes. Under the Credit Contracts and Consumer Finance Act, lenders must assess whether the borrowing is affordable for you. Income and expenses matter as much as your score.

What happens if I pay late?

A late payment fee applies — ANZ's Cashback Platinum Visa charges $6, for example — and a single missed payment typically ends your interest-free period. New purchases then accrue interest from the transaction date.

Are credit card rates quoted with GST?

Yes. New Zealand credit card rates and fees are quoted including GST, so the number on the page is the number you pay. There's no hidden tax on top of the advertised rate.

What Matters Most

The rate on the card matters far less than whether you pay it. If you clear the statement balance every month, a card with no annual fee costs you nothing regardless of whether the headline rate is 11.95% or 29.49%. If you carry a balance, the rate is the only number that counts, and a $20 annual fee against 11.95% beats a $0 fee against 19.65% by a wide margin.

Work out which person you are before you compare cards. Then check the small print on anything promotional — Gem's 30-day selection window is the clearest example of a benefit that quietly disappears if you don't act.