ChatGPT · New Zealand
The car insurance website showed one price, but paying monthly costs more. How do I compare the total price properly?
In New Zealand, the best way to compare car insurance is to look at the total amount you’ll pay over 12 months, not just the price advertised on the website.
A lower advertised premium can become more expensive when you choose monthly payments because the insurer may charge an instalment fee, apply a payment surcharge, or use a premium-financing arrangement that adds interest.
How to calculate the real price
Use this formula for each insurer:
Annual total=all instalments+fees and surcharges+interest+other compulsory charges\begin{aligned}
\text{Annual total} ={}& \text{all instalments}\
&+ \text{fees and surcharges}\
&+ \text{interest}\
&+ \text{other compulsory charges}
\end{aligned}Annual total=all instalments+fees and surcharges+interest+other compulsory charges
Make sure you count each charge only once. If the monthly amount already includes fees and interest, don't add them again.
Worked example
Suppose the website advertises an annual premium of $900, but monthly payments cost $85.
Pay annually
$900.00
Pay monthly
$1,020.00
$85 × 12 payments
Extra cost for monthly payments
$120.00
Monthly payments cost 13.3% more over the year in this example.
Compare quotes fairly
Use this checklist for every insurer:
- Same cover: comprehensive, third-party fire and theft, or third-party only.
- Same excess: the amount you pay towards an accepted claim.
- Same insured value: agreed value or market value, as applicable.
- Same optional extras: roadside assistance, glass cover and other add-ons.
- Same payment period: compare a full 12 months, including any fees, interest or surcharges.
- Same discounts: check whether an advertised discount applies only to the first year or to annual payment.
Consumer Protection NZ recommends comparing both price and cover, rather than choosing on price alone. Car insuranceCar insurance buying guide
Check whether monthly payments really cost more
They don't always. For example, AMI says its direct-debit instalments have no extra cost, and State Insurance says it doesn't charge extra for monthly, fortnightly or quarterly payments. Explore Ways to PayInsurance Made Simpler
You can also compare quotes through Consumer NZ's car insurance guide or ask the insurer:
“What is the total amount payable over 12 months if I pay monthly, including all fees and interest, and what is the total if I pay annually?”
Want me to calculate your actual difference?
Enter the figures from the quote and I'll work out the true annual cost and how much extra monthly payments will cost.
Enter amounts in NZ dollars (NZ$).
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Captured 11 October 2026