How is a metered water bill worked out?

Where water is metered, you pay for the volume you use, measured in cubic metres, at your council's price per cubic metre, sometimes with a fixed charge on top. One cubic metre is 1,000 litres.

How much water does a household use?

Use varies widely, but a rough guide is around 150 to 200 litres per person per day, more with a garden, pool or long showers. This calculator lets you enter litres per day to estimate your bill.

How can I lower my water bill?

Shorter showers, fixing leaks, efficient appliances and careful garden watering all cut usage. Because a metered bill is directly tied to volume, reducing use translates straight into a lower bill.

Water Usage Cost Calculator

This calculator estimates what a metered water bill in New Zealand is likely to cost your household over a year and a month, based on how much water you actually use. Where a council meters supply, you are billed for the volume you use, in cubic metres, at a set price, often with a fixed charge added on top. You enter the number of people in your household, how many litres each person uses per day, your council's price per cubic metre, and any fixed annual charge from your bill or website. From these, the calculator works out your daily litres, converts that to cubic metres for the year, since one cubic metre equals 1,000 litres, and applies your price and fixed charge to produce an estimated water bill per year and per month, alongside the litres used per day and cubic metres per year behind that figure. It is useful for household budgeting, for checking whether a bill looks about right, or for testing how much a shorter shower, a fixed leak or less garden watering might save, since usage feeds directly into the total. Councils set their own pricing and rules on whether wastewater is billed separately, so check your own provider's rates for an accurate figure rather than relying on typical defaults. Treat the result as an indicative estimate for budgeting, not an exact bill.

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People in the household

Litres per person per day

Price per cubic metre

Fixed charge per year

estimated water bill per year

Per month$0

Litres used per day0

Cubic metres per year0

One cubic metre is 1,000 litres. Prices, fixed charges and whether wastewater is charged separately vary by council; check your provider. Estimate only.

How it works

The calculator multiplies the people in your household by the litres each uses per day to get daily use, scales that to a year, and converts litres to cubic metres by dividing by 1,000. It multiplies the cubic metres by your price per cubic metre and adds any fixed charge to estimate the yearly bill, then shows it per month. Because the bill tracks volume, you can test how cutting daily use lowers the cost.

Worked example

Three people using 175 litres each a day is 525 litres a day, about 192 cubic metres a year. At $2.20 per cubic metre that is about $422, plus a $250 fixed charge, for around $672 a year, or roughly $56 a month.

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Budget Calculator: your budget.

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