Free NZ Tool

MyRefix

Compare two fixed terms and find the future average rate where their estimated interest costs meet.

1
Your Mortgage
The loan you're refixing
2
Rate Source
Where are you getting your rates?
Advertised rates · checked hourly
Data checked hourly · verify eligibility with your lender · methodology
3
Compare Terms
Short fix vs long fix — what's the trade-off?
Shorter Fix
Longer Fix
Results
Your break-even analysis
⚖️

Find your break-even rate

Should you fix short or long? This tool answers that with your actual numbers.

  • Break-even rate — the average future rate where estimated interest costs match
  • Payment trade-off — how much more or less you'd pay each month
  • Scenario outcomes — what happens if rates rise, fall, or hold
Market Today
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Biggest Move This Week
No move

No tracked featured-term moves this week.

Current Spread
1.00 pp

4 years has the widest gap between the cheapest and priciest tracked-lender offers.

❓Frequently Asked Questions
How does the break-even rate work?
The break-even is the constant average rate after the shorter fix expires at which both options have the same estimated interest cost over the longer fixed-term period. If your average rate over that remaining period is below the break-even, the shorter option has the lower estimated interest cost. If it's above, the longer option does.
Should I fix my mortgage short or long in NZ?
It depends on the rate gap between short and long terms, and where you think rates are heading. A larger gap means rates need to rise significantly for the longer fix to have been worth it. Use the calculator above to find your specific break-even point — it turns this decision from a guess into a clear number.
What's the difference between Special and Standard rates?
Special rates are lower but typically require 20%+ equity (loan-to-value ratio under 80%) and may have conditions such as salary credit. Standard rates are base advertised rates, not a guarantee of eligibility. Lending criteria still apply, and borrowers with less than 20% equity may have a low-equity margin added.
How often do NZ mortgage rates change?
NZ banks can change rates at any time. The Reserve Bank currently reviews the Official Cash Rate (OCR) eight times per year, but fixed mortgage rates also respond to wholesale rates, bank funding costs and competition, so they can move between OCR decisions.
How accurate are the estimates?
The calculator uses the standard principal-and-interest amortisation formula and models monthly or fortnightly payments. It assumes no fees, offsets, extra repayments or payment changes, and one constant average rate after the shorter fix. NZ lenders generally calculate interest daily and round scheduled payments, so their quoted figures can differ slightly.
Is this calculator financial advice?
No. MyRefix is an educational tool that helps you understand the maths behind your refix decision. It doesn't account for your full financial situation, risk tolerance, or future life changes. Consider consulting a qualified financial adviser or mortgage adviser before making mortgage decisions.

How to Decide Between Short and Long Fixed Mortgage Rates in New Zealand

When your fixed mortgage term expires, you need to choose a new rate — this is called refixing. The most common dilemma: do you go short (e.g. 1 year) at a lower rate, or lock in a longer term (e.g. 3–5 years) for certainty?

The Break-Even Concept

The break-even is the constant average rate after the shorter fix expires at which both options have the same estimated interest cost over the longer fixed-term period. If your average rate over that remaining period stays below the break-even, the shorter term has the lower estimated interest cost. Above it, locking in longer has the lower estimated interest cost.

What MyRefix Does

MyRefix estimates your personal break-even using your mortgage amount, remaining term, payment frequency and the rates you enter or select. It compares interest over the longer fixed-term period and shows the future average-rate threshold at which the estimated interest cost changes sides.

How the OCR Affects Your Mortgage Rate

The Reserve Bank of New Zealand currently reviews the Official Cash Rate (OCR) eight times per year. The OCR influences mortgage rates, but fixed rates also reflect wholesale market rates, bank funding costs and competition. Banks can therefore move fixed rates before, after or between OCR decisions.

Special vs Standard Rates

Special rates are discounted rates offered to borrowers who meet specific criteria — commonly 20% or more equity (less than 80% LVR), sometimes with salary-credit or other conditions. Standard rates are base advertised rates, but lending criteria still apply and a low-equity margin may be added.

Splitting Your Mortgage

Many New Zealand borrowers split their mortgage across multiple fixed terms — for example, half on a 1-year fix and half on a 3-year fix. This hedges your bet: you get some benefit from today's lower short-term rate while protecting a portion of your loan against future rate rises. Most banks allow you to split at no extra cost.

Key Terms

Refixing
Choosing a new fixed rate when your current fixed term expires.
Break-even rate
The constant average rate after the shorter fix at which both options have the same estimated interest cost over the comparison period.
LVR (Loan-to-Value Ratio)
Your loan amount as a percentage of your property value. Below 80% LVR usually qualifies for Special rates.
OCR (Official Cash Rate)
The interest rate set by the Reserve Bank of New Zealand, which influences bank mortgage rates.
Fixed vs Floating
Fixed rates are locked in for a set period. Floating rates can change at any time but offer more flexibility (e.g. unlimited extra repayments).

The core MyRefix calculator is free. If it saved you time or helped you make a better decision:

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