The person who owns the system owns the right to the certificates. That is usually the homeowner or business that paid for it. The right is valuable: roughly $1,700 on a 6.6 kW system in Sydney in 2026, and about $3,450 on a 13.5 kWh battery, at $38 per STC. Most owners hand it to the installer as part of the sale and see it as a discount on the price. A smaller number keep it.
Whichever way you go, it helps to know what you are signing, because the assignment form is a legal document that moves real money. This guide covers it from the owner’s side.
The two ways it works
You assign the STCs to the installer or an agent. You sign the assignment form, the installer creates and sells the certificates, and the quote shows the STC discount as a line. This is the normal route. You pay less upfront, and the installer carries the wait for the money.
You keep the STCs. You pay the gross price. You, or an agent on your behalf, create the certificates and sell them on the market. You get cash instead of a discount, and you carry the paperwork and the timing. It can make sense for a business that wants to book the income separately, or for an owner who spots a gap between the discount the installer offers and the rate on the market. For most households, the assignment route is simpler.
The Clean Energy Regulator’s scheme rules say the right to the certificates sits with the owner. A form is how it moves. See should you keep or assign your STCs for the trade-off in detail.
What the numbers look like
| System | STCs (2026 install) | Value at $38 |
|---|---|---|
| 6.6 kW solar, zone 3 (Sydney, Brisbane, Perth, Adelaide) | 45 | $1,710 |
| 6.6 kW solar, zone 4 (Melbourne, Hobart) | 39 | $1,482 |
| 13.5 kWh battery | 91 | $3,458 |
A quote that is clear shows the number of STCs and the dollar value as separate lines. If the discount looks low, divide it by the number of certificates. If a 6.6 kW zone 3 quote deducts $1,300 for 45 STCs, the implied price is about $29 per STC, which is a margin the installer is keeping. That may be reasonable, since the installer carries the wait and the paperwork, but you should know. The STC calculator shows the number for your postcode, and the battery STC calculator does the same for batteries.
What to check on the assignment form
- Your name and address. The owner’s details must match the property and the system.
- The system. Size in kW or kWh, the products, the installation address.
- What you are assigning. The right to the certificates for this system, nothing broader.
- The consideration. The discount or payment you receive in return.
- The signature and date. Signed by the owner, or by someone authorised to sign for them.
- Who you are assigning to. The installer’s business name and ABN, or the agent’s.
Read it before you sign. See the assignment form resource for what a good form contains, and assignment form requirements.
The tricky cases
Tenants and landlords
If you rent, the system is almost always owned by the landlord, or by whoever paid for it. Only the owner can assign the certificates. If a tenant signs the form for a system they do not own, the claim is at risk. Where the tenant pays for the system with the landlord’s written consent, ownership should be recorded in writing before the job.
Businesses, companies and trusts
Use the legal owner’s name, not the trading name or the director’s personal name, unless that is who owns the system. Company and trust structures need the right signatory. A form signed by the wrong person is a standard reason for rejection. See why claims are rejected.
Finance, leases and power purchase agreements
If the system is owned by a financier or a PPA provider, they own the right. The customer does not assign anything. Check who the contract says owns the system, and who gets the STC value. A lease where the customer pays less because the owner has banked the STCs is a normal arrangement, but you should know the figure. See how commercial PPAs work.
Second-hand and added systems
Certificates are created once, for the system as installed. If you add panels to an existing system, the additions can create their own certificates, with their own paperwork and the deeming period at the date of the addition. A system sold with the house keeps no further right, because the certificates were created at installation.
Mid-scale commercial solar
For systems above 100 kW and up to 1 MW installed from 1 October 2026, certificates can be created with a fixed five-year deeming period, as the 2026 regulation changes provide, and applications are expected to open in mid to late November 2026. The owner holds the right, and the sums are large: about 1,727 STCs for 250 kW in zone 3, roughly $65,600 at $38. See mid-scale solar STCs.
What if the installer goes under
If you assigned the STCs and your installer fails before lodging, the claim may not have been made. If you assigned and the certificates were already created, the sale belongs to the installer’s estate. Either way, the system you paid for is still yours. Keep a copy of the form, the photos and the invoice, and tell the agent or the regulator what happened. See what to do if an installer goes bust and who owns the STCs on a solar system.
Is the rebate taxable?
Treatment depends on your circumstances. For a household that assigns the STCs and gets a discount, it is generally part of the price. For a business or an owner selling the certificates, it can be income. See is the solar rebate taxable and ask your accountant.
Common questions from owners
Can I change my mind after signing the form? That depends on the form and on consumer law, including any cooling-off rights on your contract. Ask the installer, and do it before certificates are created, because afterwards the right has moved.
What if the installer offers no discount at all? Then you may be entitled to keep the certificates. Ask whether the installer expects you to assign them, and what the price would be if you did not. The gap between the two is the value you are giving up.
Will assigning affect my warranty or my feed-in tariff? No. The certificates are a separate right from the equipment warranty and from your electricity contract.
What if I sell the house? The certificates were created at installation, so the sale of the property does not change them. The new owner has a system, not a claim.
How do I check that the certificates were actually created? Ask the installer for confirmation, and keep your paperwork. If a problem arises, the Clean Energy Regulator is the place to check how the scheme treats it.
What to do next
- Check the system’s owner on the quote and the form before you sign.
- Ask for the number of STCs, their dollar value and the installation date to be written on the quote.
- If you manage a rental property, put the ownership position in writing first.
- Installers can see how to collect a clean form in how to claim STCs and the STC scheme guide.
- For a trader that pays installers fast, see how it works.