How Much Does It Cost to Change Gas Hot Water to Electric?

Short answer: most households spend $1,500–$3,000 to change from gas to a standard electric storage hot water system, and $3,000–$6,500 for a heat pump hot water system. The low end assumes an easy swap in the same spot; the high end covers bigger cylinders, tricky access, or extra electrical work. Your out‑of‑pocket can be reduced by Federal Small‑scale Technology Certificates (STCs) and, in some states, additional rebates for heat pumps.

Typical changeover costs (line‑item breakdown)

• Supply and install — electric storage (125–315 L): usually $1,200–$2,400 for the unit and plumbing, plus electrics if needed. Total commonly $1,500–$3,000.
• Supply and install — heat pump hot water (200–315 L): commonly $3,000–$6,500 depending on brand, capacity, noise rating, and site conditions.
• Electric instantaneous (whole‑home): the unit may be $600–$1,500, but many homes need three‑phase power and substantial cabling. With upgrades, $3,500+ is common; not a typical choice in Australia.
• Electrical circuit for storage/heat pump (20–25 A, RCD): $300–$900 if a new dedicated circuit is required.
• Switchboard upgrade/RCDs: $800–$2,500 if your board is full, lacks safety switches, or wiring is aged.
• 3‑phase upgrade (if pursuing electric instantaneous): $1,500–$4,000+, distributor‑dependent.
• Off‑peak/controlled‑load meter: your retailer/distributor may charge a service fee; ask before booking.
• Tempering valve (mandatory for bathrooms): parts typically $150–$350, often included in quotes.
• Relocation or new slab/safe tray: $100–$600+ depending on pipework, drain, and concrete pad.
• Old unit removal and disposal: $50–$200.
• Gas line capping at appliance: $150–$400 by a licensed plumber/gasfitter.
• Gas meter abolishment (optional): if you’re removing all gas appliances, your retailer can arrange permanent removal; fees and lead times vary by distributor.

Which electric option makes sense?

Electric storage (resistive)

The simplest swap for most homes. A 125–315 L tank with a 3.6 kW element heats overnight on a controlled‑load (off‑peak) tariff or during the day. It’s affordable to install and works well where noise or space rules out a heat pump. Running costs are higher than a heat pump but can be kept reasonable on off‑peak. Good if you want a straightforward, low‑upfront changeover.

Heat pump hot water

Looks like a cylinder with a small outdoor compressor. Uses 60–75% less electricity than resistive storage by extracting heat from the air. Best overall choice for long‑term running cost, especially if you have rooftop solar and can time operation during the day. Check noise ratings and placement (avoid outside bedroom windows), allow condensate drainage, and ensure the unit is rated for local climate.

Electric instantaneous

Delivers endless hot water but often needs three‑phase power and thick cabling (high amperage). Installation costs can blow out with switchboard and mains upgrades, and many distributors limit capacity. Suited to specific cases; most households are better served by storage or a heat pump.

What drives the price up (or down)?

• Reusing the location: Swapping into the same spot with existing plumbing/drains is cheaper.
• Electrical readiness: A spare breaker space and adequate main supply keeps costs down. Old boards, undersized mains, or no RCDs add work.
• Access and distance: Long cable/piping runs, tight stairwells, or roof craning increase labour.
• Tariff and metering: Controlled‑load/off‑peak wiring or meter changes may involve your retailer/distributor.
• Compliance items: Tempering valve (bathrooms 50°C), pressure limiting, safe tray and drain, seismic restraint where required.
• State paperwork: Compliance certificates (plumbing/electrical) are mandatory and should be included in the quote.

Ongoing costs: gas vs electric vs heat pump

If you’re asking how much to change gas hot water to electric, factor in what you’ll spend to run it. In most Australian homes:

• Gas storage/instantaneous: You pay usage plus a fixed daily supply charge. Gas prices and supply charges vary by state.
• Electric storage: Cheapest to install; higher energy use. Running it on a controlled‑load/off‑peak tariff can significantly reduce bills. Pairing with rooftop solar helps if you can heat during the day.
• Heat pump: Highest upfront, lowest typical running cost. Many households see large bill reductions compared with gas, especially when timed to use solar.

Rule of thumb: a heat pump often uses around a quarter to a third of the electricity of a resistive tank for the same hot water output.

If you remove all gas appliances, abolishing the meter also removes the gas supply charge from your bills. If you keep other gas appliances, your plumber can simply cap the hot water branch line.

Rebates and incentives (2025/26)

Three programs commonly reduce the cost of going electric:

• Federal STCs: Small‑scale Technology Certificates reduce the upfront price of eligible heat pump (and solar hot water) systems. The value varies by your postcode zone and the system’s efficiency.
• NSW Energy Savings Scheme (ESS): Approved providers may offer discounts for installing qualifying energy‑efficient hot water (commonly heat pumps). Eligibility and paperwork are usually handled by the installer. Check the official scheme page for current rules.
• Victoria Solar Homes — Hot Water Rebate: Offers a rebate for eligible households installing a heat pump or solar hot water system. Check the official program page for eligibility and current details.

Note: Plain electric resistive storage systems are generally not subsidised by STCs. Always confirm eligibility with your installer and check the official scheme pages before you buy.

How the changeover works (step‑by‑step)

1. Site check and sizing: A licensed plumber confirms cylinder location, space, drainage, and your hot water demand. Typical storage sizes: 125–160 L (1–2 people), 160–250 L (2–4), 250–315 L (4–6). Heat pumps are commonly 200–270 L for families.
2. Electrical assessment: A licensed electrician checks switchboard capacity, cabling routes, and whether you have/need controlled‑load or timers. They’ll advise if upgrades are required.
3. Choose system and tariff: Decide between storage or heat pump, set the thermostat (60°C storage for legionella control), and pick an operating schedule. For solar PV homes, program daytime heating; otherwise consider off‑peak controlled load. See our guide to off‑peak hot water.
4. Installation day: Gas unit isolated and removed, gas line capped, new cylinder set on a slab/safe tray, valves fitted, electrics connected and tested. Typical time is half a day to a full day.
5. Commissioning and compliance: Installer sets temperature, checks for leaks, logs warranties, and issues plumbing/electrical compliance certificates.
6. Optional gas meter abolishment: If you’re fully electrifying, book meter removal via your gas retailer; allow a few weeks.

Noise, placement and climate tips for heat pumps

• Noise: Check dB ratings; place away from bedroom windows and neighbours’ quiet areas.
• Airflow: Maintain clearances so the unit can breathe; avoid tight cupboards.
• Drainage: Provide a drain point for condensate and pressure relief.
• Cold climates: Choose a frost‑rated model; defrost cycles are normal.

What to ask when getting quotes

• Is plumbing, electrical, tempering valve, slab/safe tray, and disposal all included?
• Will you organise metering/tariff changes with my retailer, or do I?
• What electrical upgrades might be needed now or later?
• Is the heat pump noise‑rated for boundary compliance at my home?
• Which rebates (STCs, NSW ESS, VIC Solar Homes) apply, and will you handle the paperwork?
• Lead times for stock and, if electrifying fully, gas meter abolishment.

Bottom line: if you want the lowest upfront price, a standard electric storage tank is typically the cheapest changeover. If you’re chasing the lowest bills and have solar, a heat pump is usually the smarter long‑term buy. Get an itemised quote from a plumber who works closely with a sparky, and confirm any metering or switchboard work before installation.