Side by side
Solar discount vs cash rebate, and retailer vs installer: who claims the STCs
In short
Most households take the STC value as an upfront discount by assigning the certificates to the seller or installer. Keeping them and selling them yourself is possible but rarely worth the paperwork. Retailer and installer are different roles, and the registered person on the claim should be clear in writing.
Two questions sit under every solar quote in Australia. First, how does the government incentive reach the customer, and second, which party in the transaction is actually entitled to it? The answers explain why quotes look the way they do.
Discount or cash
When a system is installed, STCs are created for it. The system owner is the person who is entitled to them. There are two ordinary ways to treat that entitlement.
| Upfront discount | Keep the STCs for cash | |
|---|---|---|
| What happens | You assign the STCs to the seller or installer, who sells them and passes the value on as a lower price | You keep the rights, register or arrange a sale, and receive the proceeds yourself |
| When you benefit | At purchase | When the STCs are sold |
| Paperwork | An assignment form | Registry account, evidence, sale |
| Price risk | Moves to the seller | Yours until sold |
| Typical user | Most households | Rare for households; more common for businesses |
For a 6.6 kW system in a zone 3 postcode installed in 2026, the deemed output is 6.6 x 1.382 x 5, about 45 STCs. At roughly $38 to $40 each, that is something in the order of $1,700 to $1,800 at the time of writing. Use the STC calculator for your postcode.
The catch with “discount”
Because the discount is a function of the STC price, a seller who quotes it is making a small bet on the market. How a seller values the STCs sets the price you see. A bigger “STC discount” does not mean a better deal; compare the final price for the same system. The assignment form should state who the assignee is. See our STC assignment form guide.
Retailer versus installer
These are different roles, and the difference matters for who is responsible for what.
| Retailer | Installer | |
|---|---|---|
| Role | Sells the system and contracts with the customer | Designs and installs the system |
| Accreditation | A retailer is not itself an accreditation category | Designers and installers must be accredited for the installation type, through Solar Accreditation Australia |
| Responsibility | Consumer-law obligations, the quote and the sale | Safe, compliant installation and evidence |
| STCs | May be the assignee who claims them | May also be the assignee, or supplies the evidence |
In many companies, one business does both. In others a retailer subcontracts installation. If you are an installer working for a retailer, check who the assignee is and whose evidence goes into the claim; if you are a homeowner, ask the same. For the accreditation side, see accreditation compared.
Why the numbers move
The STC price changes, and so does the deeming period: five years for 2026 installs, four for 2027, then falling to one year in 2030, when the scheme ends on 31 December. That means the same system installed in January 2027 will create fewer certificates than it would have in December 2026. Installers know this, which is why you may see sales pressure around the end of a year. It is not a trick, it is arithmetic, and the deeming period guide and our note on the 2027 change show how it works. If you are choosing between two quotes and one is dated before the change, check that the install date in the contract is the date that counts, because the install date, not the signing date, sets the certificate count. A delay in the install can cost more than a better-looking discount saves.
A fair verdict
For a household, the upfront discount is the simple option and the right one for most. Keeping the STCs is possible and may suit a business with the admin to do it. Whichever you choose, compare the final price rather than the “STC discount” line, and make sure the paperwork names who claims. We do not advise on which quote to take. For installers choosing who should handle their STCs, see self-register vs trader, /stc-trading/ and /pricing/. The glossary covers terms such as assignee and registered person.
How we wrote this. Energy Merchants is a certificate trader, so we have a horse in this race. Statements about other providers are taken from their own public websites on the date shown above and are attributed. If something here is out of date, tell the desk and we will fix it.
Sources: Clean Energy Regulator: Small-scale renewable energy systems
Questions
Before you decide
Is the solar rebate a cash payment or a discount?
What is the difference between a solar retailer and an installer?
What is an STC assignment form?
More comparisons
Keep comparing
Solar hot water vs heat pump: which is better in 2026
Solar hot water and heat pump water heaters compared for 2026: how each works, how STCs apply, running cost factors, climate and what to check before choosing.
VPP-capable vs VPP-enrolled battery: what the STC rules need
Why VPP-capable is not the same as VPP-enrolled for battery STCs, where enrolment is required (NSW BESS2, WA), and what to tell customers about retailer VPP plans.
Accreditation compared: VEU, NSW ACP, SAA and CEC for installers
VEU accreditation versus using an accredited provider, NSW Accredited Certificate Providers versus traders, and what SAA and CEC cover for solar and heat pump installers.
Compare us on the thing that matters: when the money lands.
Sign up, lodge one claim, and judge us on the settlement. No lock-in, nothing to cancel.