What happens when my fixed mortgage term ends?

Your loan rolls onto a new rate, which you can re-fix or let float. If rates have risen since you fixed, your repayments jump. Knowing the new repayment ahead of time lets you prepare your budget or look at re-fixing options.

How big is the repayment jump?

It depends on the gap between your old and new rates and your remaining balance. A rise of one or two percent on a large balance can add hundreds of dollars a month, which is why the rollover can be a shock.

Can I avoid the jump?

You cannot avoid the new market rate, but you can shop around, negotiate, split your loan across terms, or increase repayments while rates are low to reduce the balance before the rollover.

Mortgage Fixed-Rate Rollover Calculator

This calculator shows how much your mortgage repayments will jump when your fixed rate ends and your loan rolls onto a new rate, a moment that catches many New Zealand homeowners off guard when rates have risen since they last fixed. You enter your remaining loan balance, your old fixed rate, the new rate you expect to roll onto, and the remaining term in years. The calculator works out the table repayment at both rates over that remaining term and returns your old repayment, your new repayment, the extra amount you will pay per month, and the extra cost per year. Seeing the size of the jump before it happens gives you time to prepare, whether that means adjusting your budget, shopping around for a better rate, splitting your loan across different fixed terms, or paying down extra balance while your old low rate still applies. For example, a $500,000 loan over 25 years rolling from 4.49% to 5.79% lifts the monthly repayment from around $2,779 to $3,156, an increase of roughly $377 a month or $4,520 a year. Use the tool a few months before your fixed term expires so the new repayment is not a surprise. This is a repayment estimate only, based on table loan calculations, and excludes fees or lender-specific terms, so treat it as a planning guide rather than a loan offer.

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Remaining balance

Old fixed rate

New rate

Remaining term (years)

extra per month after the rollover

Old repayment$0

New repayment$0

Extra per year$0

Compares table repayments at the old and new rates over the remaining term. Shop around and consider splitting across terms or increasing repayments before the rollover. Estimate only, not a loan offer.

How it works

The calculator works out the table repayment on your remaining balance at both your old fixed rate and the new rate, over the remaining term. The difference is the repayment jump you face when the fixed term ends. Seeing it early lets you budget for it, shop around for a better rate, or pay extra now to reduce the balance before the higher rate applies.

Worked example

On a $500,000 balance over 25 years, rolling from 4.49% to 5.79% lifts the repayment from about $2,779 to $3,156 a month, a jump of roughly $377 a month or $4,520 a year.

Related calculators

Fixed vs Floating Calculator: fix or float.
Interest Rate Rise Impact Calculator: rate rises.
Mortgage Repayment Calculator: repayments.
Mortgage Refinance Calculator: refinancing.

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