Every Australian household that installs eligible rooftop solar gets the same federal incentive: small-scale technology certificates, or STCs, created under the Small-scale Renewable Energy Scheme. What changes from state to state is the postcode zone that decides how many certificates you earn, and the extra programs that some governments layer on top, such as Victorian Energy Upgrades or income-tested Solar Victoria support.
So a “solar rebate by state” search has two honest answers. The federal layer is a formula you can calculate yourself. The state layer is a patchwork that you need to check against the scheme’s own page, because eligibility rules and funding caps move more often than anything we could print here.
Layer one: the federal STC discount
The federal rebate is not a cheque from the government. It is a certificate your installer creates when the system goes live. Each STC represents one megawatt-hour of expected generation over the deeming period, and the installer sells it, so the value shows up as a lower price on your quote.
The formula is simple: system size in kW, times the zone rating for your postcode, times the deeming period in years. Anything after the decimal point is dropped.
For 2026 installs the deeming period is 5 years. The four zone ratings are:
| Zone | Rating | Where it applies |
|---|---|---|
| 1 | 1.622 | The sunniest postcodes, such as Darwin and Alice Springs |
| 2 | 1.536 | Parts of northern and central Australia and inland areas |
| 3 | 1.382 | Most capital cities and the bulk of the population |
| 4 | 1.185 | Tasmania and the coolest, cloudiest southern areas |
Check your exact zone by postcode on the Clean Energy Regulator’s zone table, because a few postcodes straddle boundaries. Our zone rating explainer walks through it.
Worked example: a 6.6 kW system in 2026
- Zone 3 (the zone most capital-city postcodes fall in): 6.6 x 1.382 x 5 = 45.6, so 45 STCs.
- Zone 1 (for example, Darwin or Alice Springs): 6.6 x 1.622 x 5 = 53.5, so 53 STCs.
- Zone 4 (for example, Tasmania): 6.6 x 1.185 x 5 = 39.1, so 39 STCs.
At a spot price around $38 to $40 at the time of writing, 45 STCs is roughly $1,700 to $1,800 of value. The same panels in Zone 1 earn about eight more certificates. The postcode matters, but not by thousands of dollars.
Layer two: what each state adds
State programs fall into three families: certificate schemes that fund upgrades, rebates and loans funded by budgets, and tariff or network rules that change what your solar is worth after it is installed.
Victoria. Solar Victoria has offered income-tested support for solar and hot water, and the household income cap fell to $150,000 on 1 July 2026. Separately, Victorian Energy Upgrades creates VEECs for certain household efficiency upgrades. See our answer on the income limit.
New South Wales. The Energy Savings Scheme and the Peak Demand Reduction Scheme create certificates for upgrades and, since the federal battery program began, a PDRS incentive for connecting a battery to a virtual power plant. Rooftop solar itself is mainly served by STCs.
Queensland and South Australia. Neither has an active state solar-panel rebate at the time of writing. Past state battery programs have closed; check the government page before relying on any advertised “state rebate”.
Western Australia. The state’s residential battery scheme sits beside the federal program. Rooftop solar still rides on STCs, and Synergy and Horizon Power set the feed-in terms.
ACT, Tasmania and the Northern Territory. Support has tended to be loans, concessional finance or targeted programs rather than a general solar-panel cash rebate. The ACT’s Sustainable Household Scheme is the best known; read the official page for current terms.
If an ad quotes a state dollar figure for solar panels, ask for the scheme name and read its conditions. Our brief rule at the desk: no scheme name, no belief.
Why the net price matters more than the rebate
Quotes rarely compare cleanly because the STC discount is applied in different ways. One installer shows the full system price then subtracts the rebate. Another shows a single net figure. A third assigns the STCs but quotes a rebate based on a low trader price, then keeps the difference.
Ask each installer for three numbers: the gross system price, the number of STCs they will create, and the dollar value they are crediting you per STC. Divide and compare. Our answer on how STC discounts are shown on quotes goes through the red flags.
Timing: the rebate falls every year
The deeming period shortens by one year each January, so a system installed in 2027 earns four years of STCs rather than five: the same 6.6 kW Zone 3 system would earn 36 STCs, not 45. The scheme ends on 31 December 2030. If you are choosing between installing in December and in February, that gap is the real cost of waiting. We cover it in what changes in January 2027.
Feed-in tariffs and network rules are the quiet state difference
The rebate gets the attention, but the state you live in often affects the long-run value of solar more through what happens after installation. Retailers set feed-in tariffs, which have fallen in most states and can be close to zero in the middle of the day. Network operators set export limits, and some states or distributors require smart inverters or limit exports to a fixed number of kilowatts per phase.
That matters when choosing system size. A larger array earns more STCs up front, but if your network caps exports at a low level, the extra panels may spend the middle of the day switched off. Ask the installer what export limit applies to your address, and whether the inverter you are being quoted can meet any dynamic export requirement. Dynamic connections and emergency backstop rules have been rolling out across several states, and an inverter that cannot comply can end up costing you a replacement.
Time-of-use tariffs are the other piece. If your retailer charges more in the evening, a battery or a larger share of daytime consumption (hot water, pool pump, dishwasher timers) changes your payback far more than a $200 difference in rebate between zones.
Reading a quote line by line
A good solar quote has six things: panel brand and model, inverter brand and model, system size in kW, the number of STCs and how they are treated, the net price after STCs, and the installation date or window. If any of these is vague, ask. The STC line should say “assigned to installer” or similar, and show the count. For the rest of the paperwork, see the assignment form guide.
What to do next
- Find your zone and calculate your STCs with the formula above.
- Read the official page for any state program you think applies, and note the date it was last updated.
- Get at least two written quotes showing STC count and the dollar credit per STC.
- If you are an installer, see how the numbers flow through STC trading, the daily rates on /pricing/ and the how it works page.