Last Chance: How to Lock In the 30% Federal Solar Tax Credit Before It Expires December 31, 2025

If you have been thinking about going solar in Maryland, Washington DC, or Northern Virginia, the next six weeks matter more than the past six years. The 30% federal Residential Clean Energy Credit, the single largest financial incentive in the history of American rooftop solar, expires after December 31, 2025. Systems placed in service on January 1, 2026 or later will not qualify.

This is not a slow phase-down. Earlier in 2025, the 30% credit was scheduled to run through 2032 under the Inflation Reduction Act. The One Big Beautiful Bill, signed into law in July 2025, accelerated that schedule and ended the residential credit (Section 25D) at the end of this year. For homeowners buying a system with cash or a loan, the cliff is real.

Here is what that means in practice for DMV homeowners, and what you need to do now if you want to lock in the 30%.

What the 30% Credit Is Worth on a Real DMV System

The Residential Clean Energy Credit is a dollar-for-dollar reduction of your federal income tax liability equal to 30% of the qualifying cost of your solar system. There is no income cap and no dollar cap for residential solar.

Stack a battery on top of any of these and the entire battery cost qualifies as well, as long as the battery is at least 3 kWh of usable capacity.

For most middle-class homeowners with a normal W-2 income and a paid-off or financed home, the credit is large enough that it cannot be used in a single tax year. The IRS allows you to carry it forward into future tax years until it is fully used.

The "Placed in Service" Rule Is What Actually Matters

This is where DMV homeowners run into trouble. The IRS does not look at when you signed the contract or when you paid the deposit. They look at when the system is placed in service, meaning fully installed, inspected, and operational at your home.

For a residential rooftop system in Maryland or DC, that usually requires:

• Final design and engineering plans complete
• Permits issued by your county or city (Montgomery County, Prince George's County, DC, etc.)
• Equipment delivered and installed on the roof
• Final electrical inspection passed
• Permission to Operate (PTO) issued by your utility (PEPCO, BGE, Dominion, or similar)

From contract signing to PTO, a typical Maryland or DC residential install takes six to ten weeks when nothing goes wrong. In November 2025, that timeline is already tight.

What You Need To Do Right Now

If you have not signed yet

Get quotes immediately. Most reputable DMV installers, including us, are now closing 2025 books or already telling new prospects that contracts signed after mid-November will not realistically be commissioned before December 31. Some companies will sign anyway and let the credit slip; others will be honest with you.

When you talk to an installer this month, ask one specific question: "Can you commit in writing to a Permission to Operate date before December 31?" If they cannot, the 30% credit is not guaranteed.

If you are already under contract

Stay in close contact with your installer's project manager. The bottlenecks at this point are almost always permits and utility interconnection, not the install itself. PEPCO and BGE both see surges of PTO applications in Q4 of every year, and 2025 will be the worst on record. The earlier your application is in the queue, the better.

Also confirm that your installer is using equipment that is currently in stock, not on a six-week back order. November and December are not the months to discover that your specific microinverter model is delayed.

If your install is already done but PTO is not issued yet

You are in the riskiest position. The IRS guidance treats placed-in-service as the date the system is fully functional and authorized to operate, not the date the panels were physically installed. If PTO does not come until January, your tax preparer will likely treat the system as a 2026 placement, which means no federal credit.

Push hard with your utility. If there is a documented delay caused by the utility (not by you or your installer), keep records. A tax professional may be able to help you make the case, but the safe assumption is that you need PTO in 2025.

What Happens After December 31, 2025

Starting January 1, 2026, homeowners who buy their solar system outright with cash or a loan get $0 federal tax credit. Period.

There is one important exception. Third-party owned systems (solar leases and Power Purchase Agreements) continue to qualify for the federal credit through 2027 because the system owner is a business, and businesses can claim the commercial Section 48E credit. The leasing company can pass some of that value to you in the form of lower monthly payments. But you do not own the system, you do not get the IRS credit directly, and your long-term economics are different.

We will be writing more about lease versus loan versus PPA in 2026 because this becomes a much more important decision. For now, if you can buy and want to own, the 30% credit is the deciding factor.

Maryland and DC State Incentives Are Not Going Away

It is worth saying clearly: the federal credit is the biggest piece, but it is not the only piece. After December 31, you still have access to:

• Maryland Solar Renewable Energy Credits (SRECs), paying $40 to $80 per megawatt-hour your system produces
• Maryland sales tax exemption on solar equipment (saves about 6% off equipment costs)
• Maryland property tax exemption on the added home value from solar
• 1:1 retail-rate net metering in Maryland and DC
• Montgomery County Green Bank financing with 0% interest for the first ten years for homes in Equity Emphasis Areas
• Maryland Solar Access Program (MSAP) grants up to $7,500 for income-qualified households

These programs continue into 2026 and beyond. The math still works without the federal credit; it just works less aggressively, and the payback period stretches by three to four years on a typical residential system.

The Bottom Line

If you have been on the fence, this is the moment. Solar makes sense for most DMV homeowners with a south, east, or west-facing roof and a normal electric bill. But it makes a lot more sense in 2025 than in 2026.