Mandatory Greenhouse Gas Reporting

Collecting data from greenhouse gas (GHG) emissions sources statewide will allow for a more focused effort to quantify GHG emissions, better inform policies to reduce GHG emissions, help assess compliance with GHG reduction programs, and assist with developing the Annual Statewide GHG Emissions Report.

Investments in clean energy and GHG emission reduction measures support healthy air quality for New Yorkers while mitigating the negative effects of climate change in the State. As part of New York’s ongoing efforts to gather information regarding sources of GHG emissions and implementation of the Climate Leadership and Community Protection Act (Climate Act), the New York State Department of Environmental Conservation (DEC) has adopted the Mandatory Greenhouse Gas Reporting Program (Reporting Program or Part 253) as recommended by the Climate Action Council’s Scoping Plan. The Reporting Program requires certain sources of GHG emissions, i.e., Reporting Entities, to annually report emissions and related data to DEC. 

View the Mandatory Greenhouse Gas Emissions Reporting Regulation.

NYS Electronic Greenhouse Gas Emissions Reporting Tool (NYS e-GGRT)

Part 253 will require Reporting Entities to report emissions via the New York State Greenhouse Gas Reporting Tool (NYS e-GGRT) annually. The NYS e-GGRT electronic reporting platform is currently being developed. This tool will be designed to simplify reporting by Reporting Entities to DEC. DEC will provide NYS e-GGRT training once the system is in place.

Last Updated: December 1, 2025

Note: the estimator tool has been updated from the previous version and the details of all updates are documented within the tool. 

Part 253 requires certain entities to report: Who Should Report?  

*Note: CO2e calculations use a 20-year global warming potential (20GWP). 20GWP is an assessment of the Global Warming Potential of GHGs over an integrated 20-year time frame.

General Regulation Information 

The Mandatory Greenhouse Gas Reporting Program, Part 253, regulatory documents are available on the Department’s regulations webpage, Proposed, Emergency, and Recently Adopted Regulations.

Part 253 contains Key Dates including: 

*Note: Emission data reports and verification statements for the 2026 emissions data year would be due in 2027.

FAQ and Fact Sheet

Public Hearings 

DEC hosted 2 virtual public comment hearings, and 3 in-person public comment hearings from June 3, 2025, to June 18, 2025.

Part 253 Verification

Verification Resources for Reporting Entities

Third-party verification is required annually for large emission sources that meet the listed thresholds.

If an emission source meets the threshold for verification, the responsible Reporting Entity is required to contract with a verification body accredited by the DEC. Verification Statements are due for the previous emissions year. For example, verification reports are due to the Department no later than December 1, 2027 for emissions year 2026, December 1, 2028 for emissions year 2027, and August 10 of each subsequent emissions year. Verification is on a three-year schedule, with full verification occurring the first year and less-intensive verification occurring the following two years. Full verification involves a site visit and closer inspection of the data. Less intensive, interim verification does not require a site visit and will only be permitted if a positive verification statement has been received in the first year of the three-year verification period.

There will be a list of Department approved verifiers and verification bodies once the Department has fully approved applicants. 

The Department is currently developing a Verification Bodies webpage where certified verifiers will be listed as they are approved and those seeking verification may apply. Verification Bodies will be able to visit the page for additional requirements.

Resources for Verifiers and Verification Bodies

Ways to Become Accredited in New York 

• Have an active accreditation from the California Air Resources Board (CARB) and complete the application and training
• Be a verifier currently employed at an ANSI accredited verification body and complete the application and training.
• Apply for and complete the New York verification training course for new verifiers (applications are not being accepted at this time)

Note: Verifiers must show they properly understand the Part 253-Mandatory Reporting Regulation by completing the necessary trainings. New York Accreditation may be limited to certain types or sources of emissions. 

Accreditation Application 

The following applications are for verifiers and verification bodies that intend to perform verification in New York. They should be completed and emailed along with any supporting documents to [email protected]. Verification bodies should include the applications of any verifiers they employ that intend to perform verification in New York. Include “Verification Application” in the subject line. Within 90 days of receiving the application, the Department will notify the applicant whether the application is approved or if additional information is required.

NY Verifier Application (PDF)

NY Verification Body Application (PDF)

The Department will send the information for required trainings to verifiers once their application has been reviewed. Training must be completed and signed off by the Department before final Department accreditation is received. Once the verifier/verification body receives final Department accreditation they will be included in the Department approved verifier list.