How do I claim my Investment Tax Credit (ITC) for a commercial solar project?
The 30% federal solar ITC allows you to deduct eligible solar costs directly from your tax liability. Claim it on IRS Form 3468 in the year the system is placed in service.
An Investment Tax Credit is a federal tax incentive that allows businesses to deduct a percentage of capital investment costs directly from their tax liability. Unlike depreciation, which spreads deductions over time, ITCs provide an immediate credit in the year the equipment is placed in service.
This general business credit can only reduce your actual tax liability — you cannot receive a refund for credits exceeding taxes owed (though there are limited carryback and carryforward provisions under current law).
The Solar Investment Tax Credit
The federal solar Investment Tax Credit is currently 30% of eligible solar system costs. This applies to solar photovoltaic systems installed on commercial properties.
Credit Percentage Timeline
The ITC percentage varies based on when construction began, per the Inflation Reduction Act of 2022: 2022-2032 at 30%, 2033 at 26%, 2034 at 22%, and 2035 and beyond at 0% (expires unless extended by Congress).
What Qualifies as a "Start of Construction"
The IRS defines construction as begun when "physical work of a significant nature" commences. Alternatively, the IRS deems construction begun once you've incurred at least 5% of the final project costs. Documentation is critical — keep detailed records of when construction activities began.
How to Claim the Solar ITC
Step 1: Verify Eligibility. Confirm that your system is solar energy property (photovoltaic or solar thermal), the system is new or newly reconstructed, you placed the system in service during the tax year you're claiming, and construction began in the appropriate year for the 30% rate.
Step 2: Calculate Eligible Costs. Eligible costs typically include solar panels and mounting equipment, inverters and electrical equipment directly connected to the solar system, labor costs for installation and assembly, and engineering and design services specific to the solar system. Ineligible costs typically include site preparation or general building improvements, financing costs and loan origination fees, and insurance and permit costs (though some jurisdictions allow these — consult a tax professional). The treatment of related costs like roof replacement or electrical upgrades is more nuanced and requires professional guidance.
Step 3: Complete IRS Form 3468. To claim the ITC, complete and attach IRS Form 3468 (Investment Credit) to your federal tax return. The form calculates the credit amount and provides supporting documentation.
Step 4: Professional Review. Given the complexity of solar tax credits and evolving guidance under the Inflation Reduction Act, have your ITC calculation reviewed by a tax attorney or CPA before filing.
Important Note on Passive Ownership
If you use a PPA or lease structure where a third party owns the system, you cannot claim the ITC — only the system owner can. This is one key financial advantage of all-cash purchases and loans: they allow you to claim the full 30% federal credit.