Is your heated towel rail costing you $200 a year?
Yes. Probably more, actually.
A standard NZ heated towel rail pulls about 80 watts of electricity. That's nothing - barely more than a desk lamp. Except that it's on 24 hours a day, 365 days a year, because the plumber who installed it wired it into the bathroom lights and nobody ever turns it off.
The actual cost
At 80 W running continuously:
- 80 W × 24 hours = 1.92 kWh per day
- × 365 days = 701 kWh per year
At the May 2026 MBIE retail rates, that works out to:
- Wellington City (37.0c/kWh): ~$259/year
- Christchurch (38.5c/kWh): ~$270/year
- Invercargill (38.8c/kWh): ~$272/year
- Auckland Central (41.2c/kWh): ~$289/year
- Balclutha (52.5c/kWh): ~$368/year
The "$200/year" number you sometimes see quoted is from older Consumer NZ articles when power was cheaper. In 2026, a towel rail left on 24/7 is comfortably $260-$370 a year depending on where you live.
The fix: a $25 timer
You don't need the rail hot at 3am. You need warm towels in the morning and after your evening shower. Two options:
- Mechanical timer switch ($25-40 at any hardware store): drop-in replacement for the wall switch. Set it to come on for 2 hours in the morning and 2 in the evening. Cuts the cost by ~80%.
- Smart plug or smart switch ($30-50): if you want to set a schedule from your phone, or turn it off entirely when you're away.
A timer paying for itself in six weeks is rare in the home energy space - this is one of the easiest savings you'll find.
Here is the arithmetic on the saving. Left on 24/7 the rail runs 8,760 hours a year. A timer set for two two-hour blocks runs it 4 hours a day, or 1,460 hours a year - about 83% less. In Christchurch that takes the annual cost from $270 down to roughly $45. A $30 mechanical timer recovers its cost in the first six or seven weeks, and every year after that is clear money. Over ten years in the same home you are looking at more than $2,200 saved on a single bathroom fitting.
How it compares to other always-on loads
The towel rail is sneaky because the wattage is small but the hours are not. It belongs in the same category as the other quiet drains that never get switched off. Here is how a year of 24/7 running stacks up at the national average rate of 42c/kWh:
| Always-on appliance | Power | kWh/year | Cost/year |
|---|---|---|---|
| Heated towel rail | 80 W | 701 | $294 |
| Second (garage) fridge | 200 W avg duty | ~450 | $189 |
| Main fridge-freezer | 150 W avg duty | ~340 | $143 |
| Wi-Fi router | 12 W | 105 | $44 |
| Standby / phantom load | ~30 W | ~260 | $110 |
The striking thing is that the towel rail - an appliance most people would not even list if you asked them what uses power in their home - tops the table. It costs more to run than the fridge keeping your food cold. For a fuller picture of the silent drains, see our note on phantom load.
Regional variation: where you live changes the bill
The rail draws the same 701 kWh wherever it is plugged in - what changes is the price of each unit. Because the cheapest and dearest NZ regions are roughly 14 cents apart per kWh, the same towel rail costs wildly different amounts depending on the line on your bill:
- Wellington at 37.0c/kWh: 701 × 0.370 = $259/year
- Christchurch at 38.5c/kWh: 701 × 0.385 = $270/year
- Invercargill at 38.8c/kWh: 701 × 0.388 = $272/year
- Auckland at 41.2c/kWh: 701 × 0.412 = $289/year
- Balclutha at 52.5c/kWh: 701 × 0.525 = $368/year
A South Otago household pays more than $100 a year more than a Wellington one to heat an identical towel. That is the clearest argument for a timer if you happen to live in one of the high-rate southern lines areas.
The mistakes that keep the rail running
Almost nobody chooses to run their towel rail 24/7 - it happens by default. The common reasons are worth naming because each one has a simple fix:
- It is wired to the light switch. Many older installs share a circuit with the bathroom light or the extractor fan, so the rail comes on whenever the room is in use - or worse, is on a separate always-live feed nobody controls. A sparky can move it onto its own switched spur in under an hour.
- "It is only 80 watts." True, but watts are not the bill - kilowatt-hours are. An 80W load is cheap for a minute and expensive for a year. The 8,760 hours are what get you.
- Nobody knows which switch it is. If the rail has no obvious dedicated switch, people leave it alone rather than risk turning off the wrong thing. Labelling the switch, or fitting a timer with a clear on/off, removes the guesswork.
- It doubles as the bathroom heater. It is a poor one. At 80W it produces less heat than a single incandescent bulb. If you want a warm bathroom, a timed fan heater or a heat pump warms the room far faster and cheaper per unit of actual heat.
What to do next
In order of effort and saving:
- Today, free: find the switch and turn the rail off. Switch it on for an hour before your morning and evening showers if you want warm towels.
- This month, ~$30: fit a mechanical or smart timer so you never have to remember. This is the set-and-forget option and captures roughly 80% of the saving permanently.
- If you are renovating: ask for the rail to be on its own switched, timed circuit from the start, and consider a lower-wattage model.
Work out your own number
Plug your region and usage into the NZ Power Bill Calculator to see exactly what your towel rail is adding to your bill, and which other always-on appliances are doing the same in the background.
Related guides
- Average NZ power bill by region (2026) - put your towel rail cost in context
- Why did my power bill suddenly double? - always-on appliances are a common culprit
- The most expensive appliances in NZ homes - where the towel rail ranks against the big hitters
- Heated towel rail running cost - the live appliance figure for your own region and rate