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Credit Card Payoff Calculator

See how long it takes to pay off your credit card and the total interest you will pay. Compare minimum payments versus fixed extra payments.

By Konstantin IakovlevPublished 28 March 2026Last reviewed
Data stays on your deviceRBNZ market data

About this calculator

This calculator implements credit card minimum payment rules from NZ Consumer Protection. Last consulted 20 March 2026. Verify the figures yourself by following the link.

Current NZ credit card rates

FY 2026-27 (typical big-4 banks)
  • Standard purchase rate: 18–22% p.a.
  • Cash advance rate: 22–25% p.a.
  • Low-rate cards: 12–13% p.a.
  • Minimum repayment: 2% of balance or $25 (greater)
  • Annual fee: $0–$500
  • Interest-free days: Up to 55 (if paid in full)

Disclaimer

This calculator provides estimates for general information purposes only. Results should not be relied upon as professional financial, tax, or legal advice. Tax rates and thresholds are based on publicly available IRD data and may change. Always consult a qualified tax agent or financial adviser for advice specific to your circumstances.

How credit card payoff time is calculated

Credit cards compound monthly at brutal rates (typically 18-22% pa in NZ). Paying only minimums can take 20+ years and cost 3× the balance in interest.

  1. 1

    Calculate monthly interest

    Monthly_interest = balance × (annual_rate ÷ 12)

    $5,000 @ 21% = $87.50 interest per month.

  2. 2

    Minimum payment trap

    Min_payment = max($25, balance × 2%)

    Paying only 2% means most goes to interest — balance barely drops.

  3. 3

    Payoff time calculation

    Months = log(payment ÷ (payment − bal × i)) ÷ log(1 + i)

    Pay more than minimum to escape interest spiral.

Worked example

Inputs: $5,000 balance, 21% APR, paying $200/mo vs minimum

Result: $200/mo = 30 months, $1,038 interest. Minimum-only = 25+ years, $11,000+ interest!

Frequently Asked Questions

What interest rates do NZ credit cards charge?
New Zealand credit card interest rates are among the highest consumer lending rates available, typically ranging from 15% to 25% per annum (p.a.). Most major bank credit cards sit in the 19.95%–22.95% p.a. range for purchases, with cash advances often charged at 21%–25%. Some low-rate credit cards charge 9.95%–13.95% p.a. but often have higher annual fees. Reward and premium cards tend to sit at the higher end of the range. Interest is usually charged daily and compounded, meaning you pay interest on unpaid interest from the previous statement. New Zealand does not have a legislated maximum credit card interest rate cap, unlike some other countries. The CCCFA requires lenders to disclose credit card interest rates, minimum repayments, and total cost of credit in the initial disclosure. Shopping around and comparing the effective interest rate after accounting for fees can make a significant difference to your costs. Source: Consumer NZ — Credit Cards; MBIE — CCCFA.
What is the minimum payment trap?
The minimum payment trap occurs when you only make the minimum monthly payment on your credit card — typically 2% of the outstanding balance or $25, whichever is greater — and your debt barely reduces while interest continues to accrue. For example, a $5,000 balance on a credit card charging 20% p.a. with a 2% minimum payment: in month one you pay $100, but $83 is interest, so only $17 reduces your principal. At this rate, it could take over 35 years to pay off the debt and cost more than $7,000 in interest alone. The minimum payment is designed to keep you in debt longer, maximising interest revenue for the card issuer. New Zealand's CCCFA requires credit card statements to include information about how long it will take to repay the balance if only the minimum payment is made. Always pay more than the minimum where possible. Source: Consumer NZ — Credit Card Minimum Payments; Commission for Financial Capability (CFFC).
Which debt repayment strategy is best — avalanche or snowball?
The two most popular debt repayment strategies are the avalanche method and the snowball method. The avalanche method prioritises paying off the debt with the highest interest rate first (while making minimum payments on all others), then rolling that payment to the next highest-rate debt. This minimises total interest paid and is mathematically optimal. For example, if you have a credit card at 22% and a personal loan at 12%, you attack the credit card first. The snowball method prioritises the smallest balance first, giving you quick wins and psychological momentum, then rolling payments to larger debts. Research suggests the snowball method can lead to better outcomes for many people because the motivational wins keep them on track. For New Zealand borrowers with credit card debt at 20%+ alongside lower-rate debts, the avalanche method typically saves more money. Choose the method you are most likely to stick with consistently. Source: Commission for Financial Capability — Debt Repayment (cffc.org.nz).
How do balance transfers work in NZ?
A balance transfer allows you to move debt from one or more credit cards to a new card — typically one offering a low or 0% promotional interest rate for a set period, usually 6 to 24 months. In New Zealand, several major banks offer balance transfer deals at 0% to 1.99% p.a. for introductory periods. For example, transferring a $5,000 balance from a 20% card to a 0% card for 12 months saves approximately $1,000 in interest, giving you 12 months to pay down the principal. Key risks include: the promotional rate expires and reverts to a high standard rate (often 19.95%–22.95%); new purchases on the card may attract the standard rate immediately; and balance transfer fees (typically 1–3% of the amount transferred) may apply. Using a balance transfer responsibly — setting up a repayment plan to clear the balance before the promotional period ends — can be a highly effective debt reduction strategy. Do not use the freed-up credit limit on your old card to accumulate more debt. Source: Consumer NZ — Balance Transfers; MBIE — CCCFA.

Shows how long it takes to pay off NZ credit card debt and total interest paid, given your balance, interest rate, and monthly payment. Makes the case for paying more than the minimum.

How this calculator works

Each month, interest accrues on the remaining balance (balance × monthly rate), then the payment is applied. Months to payoff = −log(1 − (balance × monthly rate) / payment) / log(1 + monthly rate). Minimum repayment is typically 2% of balance or $20, whichever is greater.

NZ Credit Card Key Facts

Typical NZ credit card interest rate19.95%–22.95% p.a.
Minimum repayment (typical)2% of balance or $20 (whichever is greater)
NZ average credit card debt~$2,500
Interest-free period44–55 days (purchases only, not cash advances)
Cash advance rateOften higher than purchase rate; no interest-free period

Interest-free period only applies when you pay your full balance each statement. Partial payments void the interest-free period.

Worked Examples

$5,000 balance at 20% p.a., paying only the minimum (2% or $20)

Takes approximately 32 years to repay, with around $8,000 in total interest paid.

  1. Starting balance: $5,000
  2. Monthly rate: 20% / 12 = 1.667%
  3. Month 1 minimum: $5,000 × 2% = $100
  4. Month 1 interest: $5,000 × 1.667% = $83.33
  5. Month 1 principal reduction: $100 - $83.33 = $16.67
  6. As balance falls, minimum payment falls — extremely slow payoff
  7. Total interest over ~32 years: ~$8,000
  8. Paying minimums is one of the most expensive ways to carry debt

$5,000 balance at 20% p.a., paying a fixed $200/month

Paid off in approximately 29 months, total interest ~$800.

  1. Balance: $5,000, rate 20% p.a. (1.667%/month), payment $200/month
  2. Months = -log(1 - ($5,000 × 0.01667) / $200) / log(1.01667)
  3. Months = -log(1 - 0.4167) / log(1.01667)
  4. Months = -log(0.5833) / 0.007252
  5. Months = 0.5397 / 0.007252 ≈ 29 months
  6. Total repaid: $200 × 29 = $5,800 (approximately)
  7. Total interest: $5,800 - $5,000 = $800
  8. Saving vs minimum payments: ~$7,200 in interest

Built and maintained by Konstantin Iakovlev. Data sourced from the IRD and official New Zealand government sources.

Last reviewed: