What Does a 12 kW Solar System Cost?
This 12 kW job carries $200 of fixed cost before a single unit of work is priced, and that block is 1% of the low estimate. It is why the per-kW figure here ($2,817 at the low end) is where it is rather than somewhere near the national average.
Adjust for your state
Fixed costs of $200 are included in every figure on this page, so the per-square-foot price falls as the job gets bigger.
How it compares with the next size
Going up from 10 to 12 kW adds $5,600 to $6,400 to the bill, but the per-kW price actually falls from $2,820 to $2,817. You are paying more in total and less per unit at the same time — that is the fixed cost being spread thinner.
What the number is made of
At 12 kW, the arithmetic is $200 plus 12 times 2800.0 to 3200.0 per kW. Because the fixed part does not move with the job, this page's per-kW figure of $2,817 to $3,217 would be different on a job of another size — and the tables below show by how much.
| Component | Low | High |
|---|---|---|
| Fixed costs (permits, delivery, setup) | $200 | $200 |
| Materials | $31,434 | $35,898 |
| Labor | $2,366 | $2,702 |
| Total | $33,800 | $38,600 |
The same size, five different states
Material prices do not change at the state line. Labor does. These five states sit at different points of the federal wage distribution for this trade.
| State | Labor factor | Low | High |
|---|---|---|---|
| Oklahoma | ×0.79 | $33,291 | $38,019 |
| Arizona | ×0.85 | $33,447 | $38,197 |
| West Virginia | ×0.92 | $33,611 | $38,384 |
| New Hampshire | ×1.08 | $33,980 | $38,805 |
| Illinois | ×1.40 | $34,749 | $39,684 |
Only the labor line moves between states. That is a deliberate limitation, not an oversight: state-level material pricing is not something we have reliable data for, so we do not pretend to.
By material
| Material | Low | High |
|---|---|---|
| Monocrystalline (standard) | $33,800 | $37,400 |
| Monocrystalline TOPCon | $36,200 | $41,000 |
| Polycrystalline | $31,400 | $35,000 |
Other sizes
| Size | Low | High |
|---|---|---|
| 3 kW | $8,600 | $9,800 |
| 4 kW | $11,400 | $13,000 |
| 5 kW | $14,200 | $16,200 |
| 6 kW | $17,000 | $19,400 |
| 7 kW | $19,800 | $22,600 |
| 8 kW | $22,600 | $25,800 |
| 10 kW | $28,200 | $32,200 |
| 12 kW ← | $33,800 | $38,600 |
Does a big system need a service upgrade?
Often. Larger arrays and batteries can push an older 100-amp service past its limit.
How much roof space does it need?
Roughly 100 square feet of usable roof per kilowatt, depending on panel efficiency and orientation.
Is the price per watt lower at this size?
Slightly. Solar is unusually linear, because equipment scales with size and there is little fixed cost to spread.
Is 12 kW a large job?
It is the largest size we price for this project. At this size the fixed costs come to $200 of the low total, which is 1% of the bill — lower than at the smaller sizes we cover.
How much does location change the price at this size?
Between the cheapest and most expensive state in the table the total moves from $33,291 to $39,684, a difference of $6,392. Only the labor line changes; material is priced nationally.
Updated October 2026