Skip to main content
U.S. flag

An official website of the United States government

Here’s how you know

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

HTTPS

Secure .gov websites use HTTPS
A lock (LockA locked padlock) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

    • Environmental Topics
    • Air
    • Bed Bugs
    • Cancer
    • Chemicals, Toxics, and Pesticide
    • Emergency Response
    • Environmental Information by Location
    • Health
    • Land, Waste, and Cleanup
    • Lead
    • Mold
    • Radon
    • Research
    • Science Topics
    • Water Topics
    • A-Z Topic Index
    • Laws & Regulations
    • By Business Sector
    • By Topic
    • Compliance
    • Enforcement
    • Laws and Executive Orders
    • Regulations
    • Report a Violation
    • Environmental Violations
    • Fraud, Waste or Abuse
    • About EPA
    • Our Mission and What We Do
    • Headquarters Offices
    • Regional Offices
    • Labs and Research Centers
    • Planning, Budget, and Results
    • Organization Chart
    • EPA History

Breadcrumb

  1. Home
  2. Cross-State Air Pollution

Important Dates: Good Neighbor Plan NOx Ozone Season Group 3 Trading Program

2023 and 2024 Important Dates

On March 15, 2023, EPA finalized the Good Neighbor Plan for the 2015 ozone National Ambient Air Quality Standards (NAAQS). Starting in the 2023 ozone season, the rule will require additional emissions reductions of nitrogen oxides (NOX) from power plants in 22 states under the NOX Ozone Season Group 3 Trading Program. This list highlights key initial implementation dates for this program.

Note: Some courts have issued preliminary orders temporarily staying the effectiveness of EPA’s Good Neighbor SIP disapproval action (88 FR 9336) with respect to several states, and EPA is taking measures to comply with those orders. The description of the Good Neighbor Plan in this Fact Sheet reflects the rule as published, without regard to the stay orders and the measures EPA will be taking to comply with them. 


General

June 1, 2023 

March 15, 2023

June 5, 2023

Allowance transfer deadline for the 2022 control periods (applies to all CSAPR programs)

Good Neighbor Plan signed

Good Neighbor Plan published in the Federal Register

August 4, 2023

Rule effective date (see factsheet  Prorating Emissions Budgets, Assurance Levels, and Unit-Level Allowance Allocations in the Event of an Effective Date After May 1, 2023 (pdf) (200.38 KB, June 8, 2023) )

2024-2029 ozone seasons

Unit-specific backstop daily rate applies to coal-fired steam units serving generators with a nameplate capacity ≥100 MW that operate with SCR on or before September 30 of the preceding control period (except circulating fluidized bed units)

August 1, 2024

Target date for EPA to recalibrate the Group 3 allowance bank if the bank exceeds 21% of the sum of the Group 3 states’ 2024 budgets


Group 2 Allowance Recall (see factsheet Recall of CSAPR NOₓ Ozone Season Group 2 Allowances from Sources in States Newly Transitioning to the CSAPR NOₓ Ozone Season Group 3 Trading Program (pdf) (194.19 KB, June 8, 2023) )

August 21, 2023

Target date for EPA to execute first-round recalls for vintage 2023-2024 Group 2 allowances

September 15, 2023

Deadline for sources to hold allowances for second-round recalls for vintage 2023-2024 Group 2 allowances

November 15, 2023

Target date for EPA to execute any further recalls of 2023-2024 Group 2 allowances


Group 3 Allowance Recordation

September 5, 2023

Deadline for EPA to record existing unit Group 3 allocations from 2023 and 2024 state budgets for sources that have fully complied with recall (but see “State-determined Allowance Allocations for 2024 Control Period” below)

June 1, 2024

Deadline for states to submit state-determined advance allocations of vintage 2025 Group 3 allowances

July 1, 2024

Deadline for EPA to record advance allocations of vintage 2025 Group 3 allowances


Group 3 Additional Bank Creation (see factsheet Creation of an Additional Group 3 Allowance Bank for the 2023 Control Period (pdf) (142.49 KB, June 8, 2023) )

September 18, 2023

Deadline for EPA to convert vintage 2017-2022 Group 2 allowances into vintage 2023 Group 3 allowances


State-determined Allowance Allocations for 2024 Control Period

August 4, 2023

Deadline for a state to submit to EPA a letter indicating its intent to submit a complete SIP revision to modify 2024 allowance allocations  

September 1, 2023

Deadline for a state that submitted a letter of intent to submit to EPA a complete SIP revision to modify 2024 allowance allocations

September 15, 2023

Deadline for EPA to record EPA-determined default allocations for a state that submits a timely letter of intent but fails to submit a SIP revision

March 1, 2024

Deadline for EPA to record state-determined allocations for a state that submits a timely letter of intent followed by a timely SIP revision that is approved by EPA


New Unit Set-Aside (NUSA)

March 1, 2024

Deadline for EPA to publish preliminary NUSA NODA for the 2023 control periods

May 1, 2024

Deadline for EPA to publish final NUSA NODA for the 2023 control periods and record allocations

Note: If a date identified above is not a federal business day, the applicable date will generally be the next federal business day.

« Return to Good Neighbor Plan for the 2015 Ozone NAAQS

Cross-State Air Pollution

  • Good Neighbor Plan
  • What is Cross-State Air Pollution?
  • What Does the Clean Air Act Say?
Contact Us about Cross-State Air Pollution
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on March 4, 2025
  • Assistance
  • Spanish
  • Arabic
  • Chinese (simplified)
  • Chinese (traditional)
  • French
  • Haitian Creole
  • Korean
  • Portuguese
  • Russian
  • Tagalog
  • Vietnamese
United States Environmental Protection Agency

Discover.

  • Accessibility Statement
  • Budget & Performance
  • Contracting
  • EPA www Web Snapshot
  • Grants
  • No FEAR Act Data
  • Plain Writing
  • Privacy
  • Privacy and Security Notice

Connect.

  • Data
  • Inspector General
  • Jobs
  • Newsroom
  • Regulations.gov
  • Subscribe
  • USA.gov
  • White House

Ask.

  • Contact EPA
  • EPA Disclaimers
  • Hotlines
  • FOIA Requests
  • Frequent Questions
  • Site Feedback

Follow.