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:

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 2025 interim 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.