Under each RGGI state's CO2 Budget Trading Program, a source (a power plant with at least one unit serving a generator with capacity 25MW* or greater located within the RGGI participating states) is required to possess CO2 allowances equal to their CO2 emissions over a three-year control period.

A CO2 allowance represents a limited authorization to emit one ton of CO2, as issued by a respective State. Each RGGI state's environmental regulatory agency uses RGGI COATS to determine compliance with state CO2 Budget Trading Program regulations, by comparing a source’s covered emissions with the allowances held in their compliance account.

*Please see New York's regulation for its specific applicability criteria.


RGGI is currently in its sixth three-year control period. Three-year control periods have proceeded as follows:

Three-Year Control Period Start Date End Date
Sixth Control Period Jan. 1, 2024 Dec. 31, 2026
Fifth Control Period Jan. 1, 2021 Dec. 31, 2023
Fourth Control Period Jan. 1, 2018 Dec. 31, 2020
Third Control Period Jan. 1, 2015 Dec. 31, 2017
Second Control Period Jan. 1, 2012 Dec. 31, 2014
First Control Period Jan. 1, 2009 Dec. 31, 2011

The RGGI participating states are Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont. The state of New Jersey participated in the first control period and resumed its participation in 2020. Virginia participated from 2021 to 2023. Pennsylvania became a RGGI participating state in 2022, but it has been enjoined from taking part in auctions and enforcing compliance pending a ruling by the PA Supreme Court.

Compliance is evaluated at the end of each three-year control period. Starting in the third control period, the RGGI states have also conducted interim control period compliance, which requires each CO2 budget source to hold allowances equal to 50 percent of their emissions during each interim control period (the first two calendar years of each three-year control period).

To learn more about the fifth control period CO2 budget source compliance process, please see the documents below. An informational compliance webinar will be scheduled and materials will be posted below.

RGGI COATS provides public reports of compliance data.


Fifth Control Period Compliance Documents Format Updated
Fifth Control Period Compliance Webinar Presentation PDF 10.10.23
Fifth Control Period Compliance Checklist PDF 04.28.23
Fifth Control Period Compliance Fact Sheet PDF 04.28.23
Fifth Control Period Compliance FAQ PDF 04.28.23