How do I compare power plans in New Zealand?

Compare the daily fixed charge and the per-unit rate together against your actual usage. A plan with a low unit rate but a high daily charge can cost more overall, especially if you use less power.

What is a daily fixed charge?

It is a set amount you pay each day regardless of how much power you use, on top of the per-unit rate. Low-user plans have a lower daily charge, which can suit smaller households.

Why does my usage matter when comparing plans?

The cheapest plan depends on how much power you use. Heavy users benefit most from a low unit rate, while light users benefit more from a low daily charge. The calculator compares plans for your actual usage.

Power Plan Comparison Calculator

This New Zealand calculator helps households compare electricity plans to find the cheapest option for how they actually use power, cutting through the confusing mix of daily charges, unit rates, and discounts. You enter your typical usage and the rates of the plans you are comparing, and the tool calculates the real annual cost of each, including fixed daily charges that can make a low unit rate misleading. The breakdown shows the fixed and usage components and the total for each plan, helping you switch with confidence to the plan that genuinely suits your household, rather than the one with the best-sounding headline rate.

Your daily power usage (kWh per day)

Plan A

Daily fixed charge (cents)

Per-unit rate (cents per kWh)

Plan B

Daily fixed charge (cents)

Per-unit rate (cents per kWh)

cheaper plan for your usage (annual cost)

Plan A per year$0

Plan B per year$0

Saving$0

Charges are entered in cents to match power bills. Low-user and standard-user plans differ in their daily charge, so check which category fits your usage. This ignores prompt-payment discounts and GST nuances, which vary by retailer. Estimate only, not financial advice.

How it works

Each plan cost is the daily fixed charge times 365, plus the per-unit rate times your annual usage. Your annual usage is your daily kWh times 365. The calculator adds the fixed and usage parts for each plan and compares the totals. A plan with a low unit rate but a high daily charge can lose to one with a higher unit rate but a low daily charge, especially for lighter users, which is exactly the trap this tool reveals.

Worked example

Using 18 kWh a day, Plan A at a 69 cent daily charge and 28 cents a unit costs about $2,090 a year. Plan B at a 200 cent daily charge but 24 cents a unit costs about $2,307. Despite Plan B lower unit rate, Plan A wins here because of its much lower daily charge.

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