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Clean Air Markets

Allowance Markets

Notice: Upcoming Rulemaking May Affect CSAPR NOX Ozone Season Group 2 Allowances

Under EPA's cap and trade programs, allowances are allocated to regulated sources under an overall emissions budget that caps total emissions across all sources combined. Each allowance represents an authorization to emit one ton of emissions per allowance held in a compliance period. Anyone can transfer or purchase previously allocated allowances, including both regulated companies and members of the general public. EPA tracks allowance holdings and records transactions through CAMD Business System (CBS).

Buying and Selling Allowances

Allowances can be bought directly from a company, individual, or group who holds them, or through a broker. Additionally, SO2 allowances under the Acid Rain Program can be purchased at the annual EPA Acid Rain Program SO2 Allowance Auction. Except for the auction, EPA does not sell allowances.

Frequently Asked Questions About Allowances


Brokers bring together parties that have allowances to buy and sell. Brokers are more appropriate for higher volume allowance transactions. The following list represents the brokers and exchanges that EPA knows about. The list is based on publicly available information and may not be complete. Mention of trade names or commercial entities does not constitute endorsement or recommendation for use. If you are a broker or exchange and would like to be added to the list, please let us know.

Broker Contact Information
Name Phone                     Website
Amerex Energy 281-340-5200
BGC Environmental Brokerage Services 646-346-6899 www.emissionstrading.comExit
Element Markets LLC 281-207-7200 www.elementmarkets.comExit
Emission Advisors, Inc. 713-385-3321 www.emissionadvisors.comExit
Evolution Markets 914-323-0255 www.evomarkets.comExit
GFI Group, Inc. 212-968-6937 www.gfigroup.comExit
ICAP Energy 281-340-8300 www.icap.comExit
ICE Futures U.S. 312-836-6727 www.theice.comExit
Marex Spectron 360-892-3300 www.marexspectron.comExit
TFS Energy 212-943-2883 www.tradition.comExit

EPA's Acid Rain Program SO2 Allowance Auction

Because the availability of allowances is crucial to ensure both the economic efficiency of the emissions trading program and the addition of new electric-generating capacity, Title IV of the Clean Air Act Amendments mandates that EPA hold or sponsor a yearly auction of allowances for a small portion of the total allowances allocated each year. The auction helps ensure that new units have a public source of allowances beyond those allocated initially to existing units. Moreover, in the early stages of the regulatory program, the auction helped provide price information to the allowance market.

Once a year, EPA auctions a certain number of SO2 allowances. Utilities, environmental groups, allowance brokers, and anyone else interested in purchasing allowances can participate. Auction allowances are sold to the highest bidder until no allowances remain. Successful bidders are notified and listed on EPA’s website.

To bid in the EPA auction please see the How to Bid Factsheet in the Auction section of Clean Air Markets Forms page. 

Results of the Acid Rain Program SOAllowance Auction»

Frequently Asked Questions About EPA's Acid Rain Program SO2 Allowance Auction