This bill, titled the "Renewable Natural Gas Incentive Act of 2025," seeks to amend the Internal Revenue Code of 1986 to encourage the increased use of renewable natural gas (RNG) . Its primary goals are to reduce greenhouse gas and other harmful transportation-related emissions, improve air quality, and stimulate job creation and economic opportunity across the United States. The legislation introduces a new tax credit for RNG, providing a financial incentive for its adoption. Specifically, the bill establishes a renewable natural gas fuel credit of $1.00 per gallon, or gasoline gallon equivalent for non-liquid forms, of RNG. This credit applies to RNG sold or used as fuel in motor vehicles, motorboats, or aviation. To qualify, the RNG must be derived from biomass, produced by a registered person, and accompanied by a specific certification. The credit also extends to blended renewable natural gas under certain contractual and certification conditions. A significant provision makes this credit refundable , meaning taxpayers can receive direct payments for the credit amount from the Treasury. This ensures that the incentive benefits a wider range of producers and users. The credit and associated payments are set to terminate for any fuel sold or used after December 31, 2035 . Furthermore, the bill mandates that persons producing RNG must register with the Secretary of the Treasury. It also clarifies that the credit will not apply to RNG produced outside the United States for use outside the United States, and it integrates RNG into existing rules regarding double benefits and energy equivalency.