The 1 January 2027 battery rebate cut, in dollars

The federal battery rebate is paid as small-scale technology certificates (STCs), and the number you get depends on your battery's usable capacity and the date it is installed. Right now the rate is 6.8 certificates per usable kWh. From 1 January 2027 the Clean Energy Regulator's published schedule takes it to 5.7. That is the whole change: same program, same size tiers, same installer paperwork, fewer certificates per kWh.

This page is only about that one cut. If you want every step from launch in 2025 to the program's end in 2030, read when does the battery rebate end? For how the discount works in general, see the federal battery rebate, explained.

What the January 2027 cut costs, by battery size

The size tiers do not change on 1 January. The first 14kWh of usable capacity still earns the full rate, capacity from 14 to 28kWh earns 60% of it, and 28 to 50kWh earns 15%. So a 15kWh battery is counted as 14.6 "full-rate" kWh and a 20kWh battery as 17.6. Here is the federal discount before and after the cut, at the $36 to $40 certificate price we use across this site:

How we worked it out: usable kWh (tier-weighted above 14kWh) × the certificate rate × $36 to $40 a certificate, with the certificate count rounded down to a whole number (that's how they're created), and dollars rounded to the nearest $10. These are the federal discount only. Any state incentive is a separate number.

What we cannot tell you: the January certificate price

The certificate count is fixed by law. The dollar value is not. STCs trade on an open market, and the government's STC Clearing House buys them at a fixed $40 (excluding GST), which in practice acts as a ceiling. Your installer usually prices the rebate a little under that once their trading costs come out, which is why we show $36 to $40. Nobody knows the exact January price today, so treat the table as honest ballparks. The drop in certificates, though, is certain: 11 fewer on a 10kWh battery, about 15 fewer on a 13.5kWh one.

Installed, not ordered: the rule that catches people out

This is the question that matters most, and the answer is clear. The Clean Energy Regulator said it directly before the May 2026 cut: rebates are determined by the installation date, not when a contract is signed. The same rule applies on 1 January.

• Signing a contract in December does not lock in 6.8. Neither does paying a deposit, or paying in full.
• The date that counts is when the battery is installed and tested. The regulator checks that the installer's completion photo matches the test date on the electrical certificate of compliance, so a half-finished job on 31 December is not an installed battery.
• The paperwork can come later. Installers have up to 12 months after installation to create the certificates, and the number is set by the install date. A battery installed on 20 December with certificates lodged in February still gets the 6.8 rate.
• Quotes should say which rate they assume. If your install is likely to land in January, a quote priced on 6.8 is wrong, and you want to know that before you sign, not after.

One more honest point from the May cut: the regulator warned retailers that if they agree to install before a change and cannot deliver, they may be liable to pay the difference. If an installer promises you a December date, ask them to put in writing who covers the gap if it slips.

How long it realistically takes

A battery install is usually a one-day job, but getting to install day takes longer. Here is the usual path, from first quote to certificates:

Why December is the hard month

Before the 1 May 2026 cut, industry reporting had good installers booked out for weeks to months, with jobs quoted on the old rate rolling past the deadline. December adds its own squeeze: every household trying to beat the cut, plus the usual Christmas and New Year shutdowns. If a December install matters to you, the realistic window to start is October or early November, not the week before Christmas. More detail on the steps is in our battery installation guide.

Should you rush to beat the cut?

Straight answer: rush the decision, not the install. Here is how we would think about it.

• If a battery already stacks up for your home, high evening use, a low feed-in tariff, decent solar, then getting it in before 1 January is worth a few hundred dollars on a typical battery. That is real money, and starting quotes now gives you the best shot at a December date without cutting corners. Check the numbers for your home in our savings calculator.
• If you are genuinely unsure, $400 is not a reason to buy the wrong battery. A battery that is the wrong size, or on a poor quote, costs you far more over ten years than the cut does. See what a battery costs by size first.
• If the only December slot is a rushed one, take January. The regulator urged installers not to rush jobs to beat the May cut, for good reason. A safe, properly commissioned install at 5.7 beats a sloppy one at 6.8.
• If cash flow is the hold-up, look at the finance options carefully, and read the fine print on anything sold as "free".

Also worth knowing: the schedule has already changed once outside the usual cycle, when May 2026's cut was brought in mid-year. What we have described is the published schedule as at September 2026. It could change again, and we will update this page if it does.

Your state incentive is a separate story

The 1 January cut applies to the federal discount only. State and territory incentives, like VPP payments in NSW and SA or WA's rebate, run on their own budgets and rules. They are not tied to this date, although some have their own caps and closing dates. We keep the federal discount and your state incentive as two separate numbers, never added together into one headline. See what applies where you live on our battery rebates by state page.