What a home battery costs installed in 2026, and what moves the price

Two yardsticks, and why they disagree by about $5,000

The first yardstick is a model. The 2025 Annual Technology Baseline from the National Laboratory of the Rockies builds the cost of a representative residential battery, a 5 kW, 12.5 kWh lithium iron phosphate system, from its parts: the battery cabinets, the inverter, the electrical and structural hardware, labour, permitting, tax, overhead, contingency and profit. Its 2024 cost comes to $885 per kWh in 2023 dollars, or about $11,060 for the 12.5 kWh system. A model like this is a cost for a competent installer working efficiently; it is not a survey of what homeowners were charged.

The second yardstick is what owners paid. Lawrence Berkeley National Laboratory's 2026 data update compares the installed prices of solar systems sold with and without a battery in 2025. Among cash purchases, the median price of a paired solar-plus-storage system was $2.1 per watt of solar capacity higher than a solar-only system. The lab expresses it per watt of panels so the two can be compared, and it does not publish the solar size of the paired systems, so turning it into a battery price needs a stated input. Using 7.7 kW, the lab's 2025 median for all residential systems, the difference is about $16,170. California, the source of most paired-system records, has a smaller median system size than the national figure, so this conversion may overstate the battery's share. The lab's median paired battery was 13.5 kWh, which puts that illustration near $1,200 per kWh.

The two numbers measure different things, and the reasons they differ are what a buyer can act on. The model is in 2023 dollars and the sales data in 2025 dollars. About 80 percent of the lab's paired-system price records come from California, so the median mostly reflects one state's market. The paid price carries everything a real project adds: a gateway or transfer switch, a sub-panel for backed-up circuits, sometimes a main panel upgrade, the installer's actual sales costs and margin. And the paid difference is measured against a solar-only system from the same market, so any extra the battery makes the installer charge on the solar side lands in it too. None of these is measured separately, so read the gap as the room a quote has to explain, not as a markup to accuse.

Inside the modelled price: ten line items

The model's breakdown is the most detailed public itemisation we found, and its proportions are more durable than its total. Just over half the price is the battery cabinets themselves. The next largest block is not the inverter but the electrical balance of system, the model's EBOS line, at about a sixth of the total. Profit is the third largest line, at about an eighth. Permitting and interconnection is under 1 percent in the 2025 model.

Two lessons follow for anyone reading a quote. First, in the baseline's own cost formula only the battery pack is charged per kWh; balance of system is charged per kW of power, plus a fixed amount per system. So a quote that adds kWh at the same power rating should add mostly battery cost. Second, the electrical line is where projects diverge: a battery that backs up two circuits through a small sub-panel and one that backs up the whole house through a gateway with a large transfer capability are different electrical jobs, and that difference shows up in this block long before it shows up in the battery's capacity. Ask the installer which loads the system will back up, because the answer prices the electrical work.

The 2024 edition's bottom-up model (Ramasamy et al., 2023) covered only alternating-current-coupled systems, a configuration typical of adding storage beside solar; the 2025 edition's model (Cole et al., 2025), which produced the figures above, does not restate the coupling.

Why a small battery costs more per kWh than a large one

Some of a battery project's cost is the same whether the battery holds 10 kWh or 27. The 2024 edition of the same baseline published its input assumptions per system, in 2022 dollars, and four of them do not grow with capacity: $3,851 per installation for sales and marketing, $2,285 for overhead such as rent, equipment and staff, $1,633 for permitting, inspection and interconnection (including a $286 permit fee), and $95 for engineering design and stamped drawings. Together that is $7,864 per project before a single kWh of storage is bought. The scaling parts came from separate per-kWh inputs: a battery pack at $283 per kWh and a bidirectional inverter at $183 per kWh, converted for the 5 kW, 12.5 kWh reference system.

Spread the fixed $7,864 across different sizes and the effect on the price per kWh is large. It is about $786 per kWh on a 10 kWh battery, $583 on 13.5 kWh, and $291 on 27 kWh. That is the arithmetic reason a second module added in the same project costs far less per kWh than the first, and why a small battery bought only for a few hours of backup carries a high price per kWh even when everything about the installation is fair.

The table uses the 2024 baseline's inputs in 2022 dollars and is an illustration of structure, not a 2026 price. The 2025 figure carries permitting and interconnection at about $6 per kWh, roughly $75 for the reference system, against $1,633 per project in the 2024 inputs, so the two editions disagree on the size of the fixed block; the structural point holds either way. The 2025 baseline reorganised its categories, and its chart has no separate sales and marketing bar, so the two editions should not be added together. The practical lesson survives the change of format: adding capacity inside one project is cheaper per kWh than adding it in a second project later, because the second project pays the fixed block again. If you think you may want more storage within a few years, price the larger size now, then decide.

kWh and kW: two numbers on the quote, priced differently

Every battery has two ratings, and a quote should state both. Energy capacity, in kWh, is how much the battery stores: how long it can run your loads. Power, in kW, is how fast it can deliver: how many loads it can run at once, and whether it can start a well pump or an air conditioner compressor. The baseline's cost formula treats them separately, with a battery pack cost per kWh of energy and a balance-of-system cost per kW of power, plus a fixed constant, which is the formal version of the fixed-cost table above.

The market moved on the power side in 2025. Berkeley Lab found that the median residential battery paired with solar stayed at 13.5 kWh, similar to the year before, but that kW sizing increased significantly, which the lab attributes to a widely sold model with a much higher discharge rating than its predecessor. More power per kWh is worth paying for if the backup plan includes large motor loads, and not worth paying for if the battery's job is to shift solar into the evening on a time-of-use rate. The outage guide explains why the loads you choose to back up, not the battery's capacity alone, decide what the system can run.

What a paid price includes that the battery's spec sheet does not

A battery quote is a small construction project, and the lines below are where two quotes for the same battery model separate. Ask for each one by name. Where a line is missing, ask whether it is included, excluded, or not needed for your house, and get the answer written on the quote. Site work set by the battery's location belongs there too: fire-rated drywall in an unfinished basement, a heat detector or bollards in a garage, which the code rules on where a home battery can go spell out.

The last line deserves emphasis because it is invisible on a monthly-payment quote. Berkeley Lab found that loan-financed solar systems were priced considerably higher than cash purchases in 2025, potentially in part because loan origination fees were rolled into the up-front price, and the same question applies when a battery is financed. The dealer fee guide shows how to recover the cash price when a quote only shows a payment, and the panel upgrade guide covers the main-panel line.

Battery now with the panels, or added later

More buyers chose the first answer in 2025. Berkeley Lab found that the share of new residential solar systems installed with a battery rose from 25 percent in 2024 to 37 percent in 2025, driven largely by California but with large increases in Arizona and Texas, and with Hawaii and California keeping the highest rates. The lab notes that these attachment rates do not count batteries added to existing systems, so the share of solar homes that end up with storage is higher than these rates alone show.

Buying both at once avoids paying a second set of the per-installation costs the baseline lists, and it lets the system be designed around the battery from the start. It also changes the solar design. The lab found a significant decline in 2025 in module-level power electronics, microinverters and optimizers, on new residential systems, and tied it to the shift toward a battery system with an integrated inverter whose typical direct-current-coupled configuration does not readily allow them. Adding a battery later usually means an alternating-current-coupled battery beside the existing inverter, which is a well-trodden path with its own costs and constraints, covered in the guide to adding a battery to existing solar. Neither route is wrong. The cheaper one is whichever matches a decision you would make anyway, and the expensive one is a second project bought to fix a first one.

Should you wait for battery prices to fall?

The same baseline publishes three projections for residential batteries, and they are a useful check on the advice to wait. They are built from the same review of 16 cost projections, published in 2023, 2024 and early 2025, that the laboratory uses for utility-scale batteries, because it notes that cost data and projections for distributed batteries are very limited. For the 5 kW, 12.5 kWh reference system, the moderate scenario has the overnight capital cost falling 26 percent between 2023 and 2035, the advanced scenario 55 percent, and the conservative scenario rising 5 percent. Spread over those 12 years, the moderate path is a decline of about 2.5 percent a year, the advanced path about 6.4 percent, and the conservative path a slow increase.

Set that against what waiting costs. On the moderate path, a year's delay saves about 2.5 percent of the price, roughly $274 on the modelled $11,060, while giving up a year of whatever the battery was bought to do: a year of time-of-use shifting, a year of outage cover, or a year of a state incentive that may close; the battery incentives guide records California's SGIP small residential storage budget reading Closed on October 23, 2026. The laboratory also notes that most of the projected decline comes from the battery pack, with little expected from installation and the other balance-of-system costs, which is the fixed block this page already showed is a large share of a small battery's price. Waiting suits a buyer with no outage risk and no tariff gap to exploit. For anyone else, the projections argue for buying the right size once, not for buying later.

The cost of each kWh a battery actually delivers

An installed price only becomes comparable to anything once it is divided by what the battery will do. The baseline gives the inputs for that division: a 15-year lifetime, an assumption of about one full cycle a day, and a round-trip efficiency of 85 percent, which means that for every 100 kWh put in, 85 come back out, so each delivered kWh needs about 1.18 kWh of charging energy. That loss falls on the charging side: the usable kWh on a spec sheet is already energy out. Divide the modelled $11,060 by the energy a 12.5 kWh battery delivers over 15 years at different rates of use and the answer swings by a factor of fifteen.

Read the chart against why you are buying. A battery that cycles every day to move midday solar into an expensive evening period delivers its kWh at about 16 cents each on the model's price, before maintenance and before the charging energy; whether that pays depends on the gap between your evening rate and what your exports earn, which the rate guides on EnergyBS cover. A battery kept full for outages and cycled 25 times a year delivers each kWh at several dollars; it is insurance, and it should be judged as insurance, by the outages it covers and what they would otherwise cost you. Many purchases serve both jobs, and the honest description of the purchase names both.

Two adjustments make the arithmetic stricter. The baseline adds fixed operation and maintenance of 4 percent of the capital cost a year, the spending needed to keep the battery at its rated capacity across its life; over 15 years that is 60 percent of the purchase price, undiscounted, and the table under the chart shows the result. And the 2025 sales median sits above the model, as the first section showed, so your own figure belongs in the division in place of $11,060: divide your quoted price by usable kWh, by your expected cycles a year, and by the warranty years you trust, which at a cycle a day may be fewer than the certificate says once the warranty's throughput cap is divided out. The charging energy is a separate cost: your rate for that energy times about 1.18.

The credit that is no longer in the price

A battery price with 30 percent subtracted is out of date for a battery installed now. The Internal Revenue Service's page on the residential clean energy credit, read on October 24, 2026, says the credit equalled 30 percent of the cost of qualified property installed from 2022 through December 31, 2025, that battery storage of at least 3 kWh qualified from 2023, and that the credit is not available for any property placed in service after December 31, 2025. A battery installed in 2026 has no federal residential credit, so every price on this page is the price, and any quote whose net figure beats its gross figure by exactly 30 percent is using a rule that has ended.

What remains is state and utility money, which arrives in different forms: up-front rebates per kWh, performance payments for letting the utility dispatch the battery, and bill credits. The battery incentives guide reads each major program's status with its date, and the virtual power plant guide explains what the dispatch programs ask in return, because a payment for cycling the battery also uses up some of its warranted life.

Testing a battery quote against both yardsticks

Here is the test worked with stated inputs. A quote offers a 13.5 kWh battery with a whole-home gateway, added to a solar project, for $19,500 installed, cash. Step one is the price per kWh: $19,500 divided by 13.5 is about $1,444 per kWh. Step two places it: that is about 63 percent above the model's $885 per kWh, which was in 2023 dollars for a smaller 12.5 kWh system, and about 20 percent above the roughly $1,200 per kWh the 2025 sales-data illustration gives. Step three asks the quote to explain the gap with lines from the table above. Ask which lines make up the difference; a gap the quote cannot explain line by line is a reason to get a second quote, not a verdict.

Step four is the delivered-energy check. At 365 cycles a year for 15 years, the $19,500 battery delivers about 73,900 kWh, roughly 26 cents each before maintenance and charging energy. At 50 cycles a year for backup and occasional peak shaving it delivers about 10,100 kWh, roughly $1.93 each. Whichever line describes your intended use is the one to set against your rate gap or your outage history. Nothing in this test depends on a brand or an installer, which is the point: it works on any quote, and it gives you specific lines to ask about rather than a feeling that the price is high.