The federal Residential Clean Energy Credit (Section 25D) ended for expenditures made after December 31, 2025, and the IRS treats an expenditure as made when installation is completed (IRS FS-2025-05). Federal tax credits for this work have ended, but state, local and utility rebates may still apply; check what is available at your address with the DuloCore rebate calculator. A $25,000 system installation in 2026 qualifies for a $7,500 credit. But only 3% of homeowners know this credit exists, leaving billions in tax savings unclaimed every year according to Department of Energy data.
What is the geothermal federal tax credit and how much money can you get?
The Inflation Reduction Act geothermal tax credit provides 30% of total installation costs for qualifying ground-source heat pump systems installed between 2022 and 2032, decreasing to 26% in 2033 and 22% in 2034, with no maximum dollar limit for residential properties.
And this credit covers more than just the heat pump unit itself. Installation costs, ductwork modifications, ground loop excavation, thermal storage equipment, and balance-of-system expenses all qualify for the 30% credit. A complete geothermal system installation typically runs $15,000 to $40,000 depending on home size and soil conditions. So a $30,000 installation generates a $9,000 federal tax credit.
The credit applies to primary residences, second homes, and new construction projects. But the system must meet Energy Star certification requirements and connect to a dwelling unit located in the United States. The federal Residential Clean Energy Credit (Section 25D) ended for expenditures made after December 31, 2025, and the IRS treats an expenditure as made when installation is completed (IRS FS-2025-05).
"Geothermal heat pumps are the most energy-efficient, environmentally clean, and cost-effective space conditioning systems available." — U.S. Department of Energy
Are you eligible for the geothermal federal tax credit in 2026?
The federal Residential Clean Energy Credit (Section 25D) ended for expenditures made after December 31, 2025, and the IRS treats an expenditure as made when installation is completed (IRS FS-2025-05).
Three requirements determine eligibility. First, the system must be installed in an existing home or new construction you own in the United States. Second, the equipment must meet Energy Star Most Efficient certification standards or International Ground Source Heat Pump Association specifications. And third, you must have sufficient tax liability to claim the credit.
This tax credit is non-refundable, meaning it reduces your tax bill to zero but doesn't generate a refund beyond what you owe. But unused credit amounts roll forward indefinitely to future tax years until fully claimed. So a taxpayer with $4,000 in tax liability claiming a $9,000 credit uses $4,000 in the current year and carries forward $5,000 to offset future tax bills.
Renters don't qualify since they don't own the property. And landlords can't claim residential energy credits for rental properties unless they also live in the dwelling unit.
How do you apply for the geothermal federal tax credit?
Form 5695 only covers qualifying work completed by December 31, 2025 and claimed on a 2025 return; the federal 25C and 25D credits ended after that date (IRS FS-2025-05).
The application process requires five steps. First, complete the geothermal system installation and obtain a Manufacturer's Certification Statement verifying Energy Star compliance. Second, calculate 30% of total qualified expenses including equipment and installation labor. Form 5695 only covers qualifying work completed by December 31, 2025 and claimed on a 2025 return; the federal 25C and 25D credits ended after that date (IRS FS-2025-05). Fourth, transfer the calculated credit to Schedule 3 (Form 1040), line 5. And fifth, file the tax return by the standard deadline (April 15 for most taxpayers) or request an extension.
Don't attach receipts or certification documents to your tax return. But keep detailed records including contracts, invoices, certification statements, and proof of payment for at least three years after filing in case of IRS audit.
Use our free rebate calculator to estimate your total savings from federal, state, and utility incentives before installation.
Can you stack the geothermal tax credit with other incentives?
The federal geothermal tax credit stacks with state rebates, utility incentives, and local programs without reduction, allowing homeowners to combine multiple funding sources for a single installation project in 2026.
California homeowners access particularly strong stacking opportunities. The federal 30% tax credit (this federal credit ended for property placed in service after December 31, 2025) combines with California Energy Commission rebates, local utility heat pump programs, and property tax exclusions under California Revenue and Taxation Code Section 73. A $28,000 geothermal installation in California generates $8,400 in federal tax credits plus $3,000 to $5,000 in utility rebates.
The federal Residential Clean Energy Credit (Section 25D) ended for expenditures made after December 31, 2025, and the IRS treats an expenditure as made when installation is completed (IRS FS-2025-05). Installing a hybrid system that combines geothermal and air-source technology requires allocating costs between the two credit types based on equipment specifications.
What documentation do you need to claim the geothermal tax credit?
IRS requires homeowners to maintain itemized invoices, contractor certification statements, equipment manufacturer certification proving Energy Star compliance, proof of payment, and property ownership documentation for geothermal tax credit claims through 2026 and beyond.
The Manufacturer's Certification Statement is the most critical document. This statement confirms the geothermal heat pump meets Energy Star Most Efficient requirements or achieves the minimum Energy Efficiency Ratio and Coefficient of Performance ratings specified in IRS guidelines. And manufacturers typically provide this certification automatically, but homeowners should request it explicitly during purchase negotiations.
Contractor invoices must itemize costs separately for equipment, labor, ground loop installation, electrical work, and any other qualifying expenses. Lump-sum "turnkey installation" pricing makes credit calculation difficult and increases audit risk. So request detailed cost breakdowns before signing contracts.
Property ownership proof matters for audit defense. Title documents, mortgage statements, or property tax records establish that the taxpayer owns the dwelling where the system was installed. And for new construction, the certificate of occupancy plus purchase agreement proves the system was installed in the taxpayer's primary or secondary residence.
Is the geothermal tax credit refundable or non-refundable?
The federal geothermal tax credit operates as a non-refundable credit that reduces tax liability to zero without generating cash refunds, but allows unlimited carryforward of unused credit amounts to future tax years through 2034 and beyond.
Non-refundable status creates planning opportunities. A taxpayer with $50,000 in annual income and $5,000 in tax liability installing a $30,000 geothermal system claims the full $9,000 credit over multiple years. Year one applies $5,000 of credit, reducing tax liability to zero. The remaining $4,000 carries forward to year two without expiration.
And this differs from refundable credits like the Earned Income Tax Credit, which generate cash refunds exceeding tax owed. But the unlimited carryforward provision makes the geothermal credit more valuable than other non-refundable energy credits that expire after one year.
Tax planning matters for maximizing credit value. Homeowners installing systems late in the year can choose whether to place the system in service before December 31 or delay startup until January to match credit timing with higher-income years. And retirees with minimal tax liability should coordinate installation timing with Required Minimum Distribution years that increase taxable income.
Explore energy tax credits available for other home improvements including insulation, windows, and electrical panel upgrades.
Official Sources
- U.S. Department of Energy - Geothermal Heat Pumps — Technical specifications, efficiency ratings, and installation guidance for ground-source heat pump systems
- IRS Energy Efficient Home Improvement Credit — Official tax credit guidance, Form 5695 instructions, and eligibility requirements (note: the federal 25C and 25D credits ended for projects completed after December 31, 2025)
- Database of State Incentives for Renewables & Efficiency — Comprehensive database of state, local, and utility rebate programs that stack with federal credits
Related Reading: Learn more about Geothermal Carryforward Tax Credit Rules and Geothermal Tax Credit For New Construction.
Frequently Asked Questions
Am I eligible for the geothermal federal tax credit?
The federal Residential Clean Energy Credit (Section 25D) ended for expenditures made after December 31, 2025, and the IRS treats an expenditure as made when installation is completed (IRS FS-2025-05). Renters and landlords don't qualify for rental properties. And the system must be placed in service between January 1, 2022 and December 31, 2034 with the credit percentage decreasing to 26% in 2033 and 22% in 2034.
How much is the geothermal federal tax credit worth?
The federal Residential Clean Energy Credit (Section 25D) ended for expenditures made after December 31, 2025, and the IRS treats an expenditure as made when installation is completed (IRS FS-2025-05). A $20,000 installation generates a $6,000 credit, while a $35,000 system creates a $10,500 credit. Qualified expenses include equipment, installation labor, ground loop excavation, electrical work, and balance-of-system components. But the credit is non-refundable, meaning it reduces tax liability to zero without generating cash refunds beyond taxes owed.
What documents do I need to claim the geothermal tax credit?
IRS requires homeowners to maintain itemized contractor invoices, Manufacturer's Certification Statement proving Energy Star compliance, proof of payment through canceled checks or credit card statements, and property ownership documentation. Don't attach these documents to your tax return, but keep them for three years minimum in case of audit. And contractors should provide the Manufacturer's Certification Statement automatically, but request it explicitly during contract negotiations to avoid documentation gaps.
When is the deadline to claim the geothermal federal tax credit?
The credit must be claimed on the federal tax return for the year the system was placed in service, typically by April 15 of the following year or the extended deadline if filing for an extension. Form 5695 only covers qualifying work completed by December 31, 2025 and claimed on a 2025 return; the federal 25C and 25D credits ended after that date (IRS FS-2025-05). And unused credit amounts carry forward indefinitely to future tax years, so there's no expiration deadline for claiming carried-forward credits.
How does the geothermal tax credit compare to other renewable energy credits?
The geothermal credit provides 30% of costs with no dollar cap, matching the solar photovoltaic credit but exceeding the $2,000 annual limit on heat pump rebates from other programs. And geothermal qualifies for higher credit percentages than traditional HVAC upgrades which received 30% of costs up to $600 under the expired Section 25C program. The federal Residential Clean Energy Credit (Section 25D) ended for expenditures made after December 31, 2025, and the IRS treats an expenditure as made when installation is completed (IRS FS-2025-05).
Ready to calculate your geothermal savings? Use our free rebate calculator to estimate your total federal, state, and utility incentives for geothermal heat pump installation. Enter your zip code, home size, and system type to get personalized savings estimates in under 60 seconds.
Last reviewed: April 14, 2026. Reviewed by DuloCore Energy Specialists. About the team.
Check your California heat pump rebate eligibility — see the programs you qualify for and the dollar amounts on our California heat pump rebate finder.