Solar Panel Cost in Montana (2026): Price, Payback, Incentives

Q: How much do solar panels cost in Montana?

At the state median installed price of $3.60 per watt (estimate), a 7.6 kW (estimate) system that covers a typical home's use costs about $27,400 (estimate) before incentives. Quotes vary with roof, equipment and installer.

Solar Panel Cost in Montana

A typical Montana home uses 852 kWh a month^[1] of electricity. Covering that with solar takes a system of about 7.6 kW est.^[1,2], which costs roughly $23,500 to $31,500 est.^[1,2,3] before incentives at the state's median installed price. With Montana's average residential price of 14.13¢ per kWh^[4], our model puts payback at about 16 years est.^[1,2,3,4,5]. Your quote, roof and utility plan will move these numbers, so treat them as a starting point.

Montana solar at a glance

Average electricity price14.13¢/kWh^[4]Jan–Aug 2026 average (preliminary)

Average home use852 kWh/mo^[1]2024 average

Solar output per kW1,344 kWh/yr^[2]PVWatts estimate for Billings

Median installed price$3.60/W^[3]Estimate, before incentives

Typical system7.6 kWSized to cover 100% of use

Typical price$27,400Estimate, before incentives

Year-1 savings$1,440Estimate

Payback16 yearsEstimate, cash purchase

Estimates use the inputs above and the assumptions in our methodology: Montana net metering: exports credited at the retail rate (statewide rule; your utility's tariff may differ). Prices rise 2.5% a year; panels lose 0.5% a year.

Solar cost in Montana by system size

Same assumptions as the typical home above; only the system size changes. Prices are the state median before incentives and include the incentives our calculator applies by default in Montana.

Estimated cost, output and payback by system size in Montana
System	Price before incentives^[3]	After incentives	kWh in year 1^[2]	Year-1 savings^[4]^[5]	Payback (years)
4 kW	$14,400	$14,400	5,380	$760	16
6 kW	$21,600	$21,600	8,060	$1,140	16
8 kW	$28,800	$28,800	10,750	$1,440	17
10 kW	$36,000	$36,000	13,440	$1,440	20
12 kW	$43,200	$43,200	16,130	$1,440	23

Incentives that lower the price in Montana

Federal · tax creditEnding soon

Business credit for leased and PPA systems (48E)

Claimed by the system owner, not the homeowner; solar must begin construction by July 4, 2026 or be in service by December 31, 2027^[6]

If a company owns the panels on your roof (a lease or power purchase agreement), that company may claim the business clean electricity investment credit and can reflect it in your price. You cannot claim it yourself.

Who: Third-party-owned systems (leases and PPAs). Ask the provider whether the price assumes this credit.
Deadline: December 31, 2027
Checked: November 5, 2026

State · loanAvailable

Alternative Energy Revolving Loan Program (Montana DEQ)

Low-interest loan up to $40,000 for up to 10 years at a fixed 3.5% (4.023% APR) for 2026; $0 down, closing costs about $250 or 2% plus ~$200^[7]

Montana individuals, small businesses, local governments and nonprofits installing alternative energy systems such as solar PV; since April 2023 demand has exceeded funds each quarter, so DEQ ranks applications.

Who: Montana individuals, small businesses, local governments and nonprofits installing alternative energy systems such as solar PV; since April 2023 demand has exceeded funds each quarter, so DEQ ranks applications.
Maximum: $40,000
Deadline: None set in the source
Checked: November 5, 2026

State · tax exemptionAvailable

Nonfossil Energy Generation Property Tax Exemption

Up to $20,000 of the appraised value of a home solar installation is exempt from property tax for 10 years after installation^[8]

Capital investment in a recognized nonfossil form of energy generation (including solar) at a single-family residential dwelling; $100,000 limit for multifamily or nonresidential buildings.

Who: Capital investment in a recognized nonfossil form of energy generation (including solar) at a single-family residential dwelling; $100,000 limit for multifamily or nonresidential buildings.
Maximum: $20,000
Deadline: None set in the source
Checked: November 5, 2026

All Montana incentives, including utility and local programs →

How Montana utilities credit your solar

Montana law requires NorthWestern Energy and Montana-Dakota Utilities to offer net metering for home systems under 50 kW: exports offset your usage kWh for kWh at the retail rate, and a month's surplus carries forward as a kWh credit on the next bill. At the end of your chosen 12-month period (starting Jan 1, Apr 1, Jul 1 or Oct 1) any unused credits go to the utility without payment, and you still pay the normal monthly customer charge.^[5]

We have not added every Montana utility yet, so the estimates on this page use the state-level rule: Montana net metering: exports credited at the retail rate (statewide rule; your utility's tariff may differ).

Full Montana net metering and export-credit rules →

Next steps

Run the solar calculator with Montana defaults and your own bill.
Montana solar incentives
Montana net metering and export credits
How to vet installers in Montana
Spot solar sales red flags and compare financing before you sign.

Frequently asked questions

How much do solar panels cost in Montana?

At the state median installed price of $3.60 per watt est.^[3], a 7.6 kW est.^[1,2] system that covers a typical home's use costs about $27,400 est.^[1,2,3] before incentives. Quotes vary with roof, equipment and installer.

How long does solar take to pay for itself in Montana?

For a cash purchase at the state's average electricity price of 14.13¢ per kWh^[4], our model estimates about 16 years est.^[1,2,3,4,5]. Your utility's export credit and rate plan matter a lot; see the export-credit table above.

Is there still a federal solar tax credit?

Not for homeowners who buy. The Federal Residential Clean Energy Credit (25D)^[9] does not apply to systems whose installation is completed after December 31, 2025. Leased and PPA systems are different: the company that owns the system may still claim a business credit.

Change log

Nov 5, 2026Monthly output per kW in Billings updated to [64.5, 78.1, 114.9, 124.0, 144.4, 151.3, 166.3, 151.8, 124.5, 99.9, 66.5, 57.6] kWh/kW/month (NREL/NLR PVWatts v8 (1 kW-DC, fixed roof mount, 20° tilt, south-facing, 14% losses, TMY weather)).

Nov 5, 2026Average solar radiation on the panels in Billings updated to 4.76 kWh/m2/day (NREL/NLR PVWatts v8 (1 kW-DC, fixed roof mount, 20° tilt, south-facing, 14% losses, TMY weather)).

Nov 5, 2026Solar output per kW in Montana (PVWatts, Billings) updated to 1343.9 kWh/kW/yr (NREL/NLR PVWatts v8 (1 kW-DC, fixed roof mount, 20° tilt, south-facing, 14% losses, TMY weather)).

Nov 5, 2026Tax Credit for Installing Alternative Energy System (repealed): now "Was up to $500 per taxpayer; repealed by the 2021 Legislature (SB 399, Ch. 503, L. 2021) - cannot be claimed after tax year 2021" (closed).

Nov 5, 2026What the rule says updated to “credited for the excess kilowatt hours generated during the billing period, with this kilowatt-hour credit appearing on the bill for the following billing period.” (Montana Code Annotated 2025, 69-8-603 Net energy measurement calculation).