Mercury Energy kWh electricity rates and energy plans

• Fixed rate: your unit price stays the same for the duration of the contract.
• Variable rate: the retailer can adjust the unit rate at any time, with at least 30 days' notice. Prices broadly follow wholesale electricity costs.
• Time-of-use: the unit price changes by period of the day — cheaper overnight and during off-peak hours, more expensive at peak times (typically 7-9am and 5-9pm).
• Spot pricing: the unit price tracks the half-hourly wholesale market. Households with flexible usage can save when prices are low, but they are exposed to spikes during cold snaps or supply shortages.

The daily fixed charge covers the cost of staying connected to the grid: network maintenance, the lines from the street to your meter and the metering equipment itself. It is billed for every day you hold an active connection, regardless of how many kWh you use.

Households using less than 8,000 kWh per year (9,000 kWh in the lower South Island) may qualify for a low-fixed-charge tariff: a smaller daily fee paired with a slightly higher unit rate. This option is being phased out by April 2027, but it is still available today and is usually a good fit for small homes and singles.

Each part of New Zealand is served by its own local lines company (Vector in Auckland, Wellington Electricity, Powerco, Aurora, Orion and more). Each lines company sets its own delivery charges based on the cost of maintaining its network — and those costs vary widely:

• Rural and low-density networks (East Coast, West Coast, parts of Otago) cost more per customer to maintain than dense urban ones.
• Networks with significant underground cabling (central Auckland, Wellington CBD) are more expensive to upgrade but suffer fewer storm outages.
• South Island networks pass through hydro-rich generation regions, which can lower the wholesale component on some plans.

For these reasons, a customer in Dunedin can pay a different rate from a customer in Hamilton on the same Mercury Energy plan.

Comparing electricity plans is not just about the headline rate. Before signing, check:

• Unit rate (¢ / kWh): what you pay for each unit of electricity. Lower is better.
• Daily charge (¢ / day): a fixed cost added every day, regardless of usage.
• Discounts: prompt-payment, direct-debit and online-billing discounts can knock 1-3% off the total.
• Contract term and exit fees: open-term plans are usually free to leave. Fixed-term plans may charge a break fee.
• Plan extras: free-power hours, EV night rates, solar buy-back, broadband bundle discounts.

Always cross-check your offer against several retailers using your real ICP and a 12-month consumption history before signing — the headline rate alone never tells the full story.

Under the standard terms used by most New Zealand retailers, variable rates and daily charges can be adjusted at any time, with at least 30 days' written notice to the customer. Notice is usually sent by email, on the bill, or via the customer portal. This 30-day minimum is industry practice rather than a hard statutory rule, so always check the price-change clause printed on the plan terms.

Fixed-term plans are different: the unit rate and daily charge are locked in for the duration of the contract (typically 12, 24 or 36 months). If you do not switch or renegotiate at the end of the term, you are usually moved onto the retailer's standard variable rate.