The Inflation Reduction Act's 30% federal tax credit for commercial solar energy systems.
The federal commercial solar tax credit is still available — but new rules under the One Big Beautiful Bill Act have created a strict timeline. To qualify for the 30% credit, your project must begin construction before July 4, 2026. This doesn't mean the system has to be finished by then — it means real, physical work must have started on the project.
Important: Simply placing a deposit or ordering equipment may no longer be enough to qualify. Under updated IRS guidance, most projects now need to demonstrate actual physical work on-site to count as "begun construction."
Bottom line: If you want to secure the federal tax credit, plan to start your commercial solar project before July 2026. Contact Solar Mason today to begin planning →
The One Big Beautiful Bill Act, signed into law on July 4, 2025, made two major changes to the federal solar Investment Tax Credit:
The 30% residential credit ended on December 31, 2025. No step-down, no transition period. Homeowners who installed systems before that date can still claim unused credits on future tax returns (IRS Form 5695). Systems installed in 2026 or later do not qualify for any direct federal residential credit.
However, homeowners can still access the commercial credit indirectly through solar leases and PPAs, where a third-party business entity owns the system and passes the tax benefit through as lower monthly payments.
The 30% commercial credit remains in effect but follows a new, accelerated timeline that did not exist under the original Inflation Reduction Act.
Here's exactly how the deadlines work:
Your project qualifies for the full 30% ITC (plus applicable bonus adders). You have 4 calendar years from the start of construction to complete and place the system in service. This is the strongest position — it gives you the most time and the full credit.
The credit is only available if the project is placed in service by December 31, 2027. This is an extremely tight window — essentially requiring the project to be both started and finished within 18 months. For most commercial projects, this is impractical.
This is the most critical detail. Under updated IRS rules, there are two ways to establish that construction has begun:
Physical Work Test: Significant physical work on the project must have started. This means actual on-site activity — not just planning, permitting, or design work. Examples include: foundation work, pile driving, racking assembly, or equipment installation.
5% Safe Harbor (Limited): For systems 1.5 MW AC or smaller, paying or incurring at least 5% of total project costs can establish the start of construction. However, IRS Notice 2025-42 eliminated the 5% safe harbor for larger projects. For most utility-scale and large commercial projects, the Physical Work Test is now the only path.
Continuity Requirement: Once construction begins, you must either maintain continuous progress OR complete the project within 4 years. Gaps in construction activity could jeopardize your credit eligibility.
The base 30% credit can be significantly enhanced with bonus adders:
Available when prevailing wage and apprenticeship requirements are met. Without compliance, the base credit drops to just 6%.
Projects using a required percentage of U.S.-manufactured components (panels, inverters, racking) earn an additional 10% credit.
Projects located in designated brownfields, former fossil fuel communities, or areas with above-average fossil fuel employment qualify for an extra 10%.
Projects in low-income communities or serving low-income households can earn an additional 10–20% credit bonus.
Maximum stacked credit: up to 70% of total project cost. Combined with MACRS 5-year depreciation, net project cost can drop to 30–40% of the gross installation price.
Starting January 1, 2026, new Foreign Entity of Concern (FEOC) restrictions affect equipment sourcing for projects claiming the ITC. At least 40% of manufactured product value must come from manufacturers that are not classified as prohibited foreign entities (including China, Iran, Russia, and North Korea).
The government is still defining specific thresholds via the Material Assistance Cost Ratio (MACR) metric. This could make some projects more expensive or create supply chain complications if equipment doesn't meet the requirements.
What this means for you: Projects that began construction in 2025 can source equipment from any country. Projects beginning in 2026 must comply with FEOC rules or risk losing credit eligibility. Solar Mason is tracking this closely and sourcing compliant equipment for all new projects.
Claim the 30% credit on IRS Form 3468. Stack with MACRS depreciation for maximum tax benefit. Can also transfer credits to other taxpayers under Section 6418.
Nonprofits, schools, churches, municipalities, and tribal governments use Direct Pay (Section 6417) to receive the credit as a cash refund from the IRS. Available through December 31, 2027.
A financing company owns the system, claims the credit, and passes the savings to the homeowner or business through lower monthly payments. The only path to federal benefits for residential installations in 2026.
Homeowners cannot claim Section 48E directly. The only way to benefit is through a lease, PPA, or similar agreement where a business entity owns the system. Cash and loan purchases no longer qualify for any federal credit.