Quick answer: how US carbon markets work
There's no single federal carbon market in the United States. Instead, you're looking at a patchwork system: state-level compliance programs like California's Cap-and-Trade and the northeastern RGGI coalition, plus the largest voluntary carbon market on the planet. Where your business sits geographically — and what sector you're in — determines which rules apply. If you operate across state lines, you might face multiple overlapping obligations and opportunities.
Use Business carbon footprint calculator to get your baseline emissions mapped before figuring out which market applies to you.
RGGI: the Northeast's carbon coalition
The Regional Greenhouse Gas Initiative is the oldest mandatory cap-and-trade program in the US. It covers CO2 emissions from power plants rated at 25 megawatts or more across participating northeastern states, including Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, and Virginia.
RGGI works through quarterly auctions. Power generators must buy enough allowances to cover their emissions, and the cap tightens over time to drive reductions. Here's where it stands:
- Auction #71 (March 2026): 18.2 million allowances offered, with a minimum reserve price of $2.69
- Auction #70 (Q4 2025): Cleared at $26.73 per allowance
- Recent trading range: $22–29 per tonne
Revenue from RGGI auctions flows back to member states, which invest it in energy efficiency programs, renewable energy, and consumer bill relief. Since 2009, RGGI has generated billions in auction proceeds while regional power-sector emissions have dropped significantly.
The program's strength is its simplicity: it targets one sector (electricity generation) with a clear, declining cap. Its limitation is scope — it doesn't cover transportation, industry, or buildings directly.
California Cap-and-Trade: the biggest US compliance market
California runs the most expansive state-level carbon market in the country. Managed by the California Air Resources Board (CARB), the program covers large industrial facilities, electricity generators, and electricity importers — anyone emitting 25,000 metric tonnes CO2e or more annually.
For the 2026 vintage, CARB has issued 133.8 million allowances. The system links with Quebec's market, creating a cross-border trading zone that increases liquidity and price stability. Covered entities can meet part of their obligations through offset credits from approved protocols, including forestry, livestock methane, and mine methane capture.
California allowance prices have historically run higher than RGGI — typically in the $30–40+ range — reflecting the program's broader coverage and tighter cap trajectory. The state aims for a 40% reduction below 1990 levels by 2030 and carbon neutrality by 2045, so expect the cap to keep ratcheting down.
Washington state and emerging programs
Washington launched its own cap-and-invest program in January 2023 under the Climate Commitment Act. It covers facilities emitting 25,000+ tonnes CO2e per year, including fuel suppliers, and generated nearly $2 billion in its first year of auctions.
Other states are watching closely. Oregon attempted a cap-and-trade bill multiple times before legislative gridlock stalled it. Several northeastern states periodically discuss expanding RGGI to cover transportation fuels. The US carbon market landscape is evolving year by year, and new programs could emerge with each legislative session.
Key takeaway: US carbon market exposure is determined by your state and sector — not a single federal rule — so businesses need to map their specific regulatory geography.
The voluntary carbon market: America's other carbon economy
The US is the single largest participant in global voluntary carbon markets. Corporations from tech giants to regional manufacturers purchase voluntary credits to meet net-zero pledges, ESG commitments, and customer expectations — with no legal mandate driving the transaction.
Four major standards dominate the US voluntary space:
- Verra (Verified Carbon Standard) — The largest global registry, covering everything from REDD+ forestry to renewable energy
- Gold Standard — Emphasizes sustainable development co-benefits alongside emission reductions
- American Carbon Registry (ACR) — US-focused, with strong protocols for forestry, soil carbon, and industrial gas destruction
- Climate Action Reserve (CAR) — North America-specific, known for rigorous quantification methodologies
Voluntary credit prices range enormously. Low-quality renewable energy credits sell for $2–5 per tonne. Nature-based projects run $8–30. High-integrity engineered removals — biochar, direct air capture — can hit $50–150+. The market is self-correcting: corporate buyers increasingly demand credits that meet ICVCM Core Carbon Principles, which is pushing low-quality inventory out.
Browse current project types and pricing trends on the carbon price tracker.
Comparing US carbon markets at a glance
| Feature | RGGI | California Cap-and-Trade | Voluntary market |
|---|---|---|---|
| Type | Compliance (cap-and-trade) | Compliance (cap-and-trade) | Voluntary |
| Coverage | Power plants ≥25 MW | Facilities ≥25,000 tCO2e/yr | Anyone |
| Geography | 12 northeastern states | California + Quebec | Nationwide / global |
| 2025–26 price range | $22–29/tonne | $30–40+/tonne | $2–150+/tonne |
| Allowances/credits | Quarterly auction | Annual allocation + auction | Project-based issuance |
| Key registries | RGGI Inc. | CARB (CITSS) | Verra, Gold Standard, ACR, CAR |
| Offset use | Limited | Up to ~4–8% of obligation | Unlimited (voluntary) |
| Penalty for non-compliance | 3× allowance forfeiture | 4× excess emissions | Reputational only |
The compliance markets have legal teeth. The voluntary market has flexibility. Understanding which you're operating in — or both — shapes your entire carbon strategy.
Worked example: a US manufacturer across multiple markets
GreenSteel Inc. is a mid-sized steel fabrication company headquartered in New York with a manufacturing facility in California and customers across 20 states. Here's how they navigate the US carbon landscape.
Step 1: Map exposure. Using Business carbon footprint calculator, GreenSteel calculates total annual emissions at 48,000 tonnes CO2e. The New York HQ (mostly office operations) contributes 1,200 tonnes. The California plant accounts for 46,800 tonnes — well above the 25,000-tonne threshold for CARB's program.
Step 2: Compliance obligations. The California facility falls under Cap-and-Trade. GreenSteel must surrender enough allowances to cover its 46,800 tonnes. At ~$35 per allowance, that's roughly $1.64 million in annual compliance costs. The company receives some free allowances based on trade-exposure benchmarks, reducing the cash outlay to about $980,000.
Step 3: Voluntary commitments. GreenSteel has publicly pledged carbon neutrality by 2030. After compliance obligations, they still want to offset the New York office emissions and supply-chain scope 3 emissions estimated at 12,000 tonnes. They purchase voluntary credits:
- 1,200 tonnes (office) × $15/tonne (verified reforestation) = $18,000
- 12,000 tonnes (supply chain) × $10/tonne (improved cookstoves, Gold Standard) = $120,000
Total annual carbon cost: $980,000 (California compliance) + $138,000 (voluntary) = $1.118 million
That number motivates real decarbonization. GreenSteel invests $2.3 million in electric arc furnace upgrades projected to cut California plant emissions by 30% over three years — a move that pays for itself through reduced allowance purchases within five years.
Key takeaway: Voluntary credits and compliance allowances serve different purposes: mixing them up can mean overpaying for the wrong instrument or falling short of legal obligations.
Federal policy: what's on the horizon?
The US has flirted with federal carbon pricing for decades without landing one. The Waxman-Markey bill passed the House in 2009 but died in the Senate. Since then, multiple carbon tax and cap-and-trade proposals have been introduced — none have passed both chambers.
What does exist at the federal level is regulatory: the EPA sets emission standards for power plants and vehicles, the Inflation Reduction Act (2022) channeled $369 billion into clean energy incentives, and the SEC has proposed climate disclosure rules that would require public companies to report emissions. These aren't carbon pricing, but they shift the economics in similar directions.
For now, the action stays at the state level. If your business is planning a five-year carbon strategy, build it around existing state programs and voluntary market dynamics rather than waiting for a federal system that may or may not arrive. Use Your footprint calculator to set your baseline and stress-test your plan against different policy scenarios.
How to get started in US carbon markets
Whether you're a compliance-covered entity or a voluntary buyer, the playbook follows the same sequence.
1. Measure your emissions. Use Business carbon footprint calculator for corporate footprints or Energy calculator for facility-level energy emissions. You can't manage what you haven't quantified.
2. Identify your regulatory exposure. Check whether your facilities fall under RGGI, California Cap-and-Trade, Washington's program, or none of the above. State environmental agencies publish covered-entity lists.
3. Reduce first. Every tonne you eliminate through efficiency, fuel switching, or process improvement is a tonne you don't need to buy credits or allowances for. The cheapest allowance is the one you never need.
4. Buy smart. For compliance markets, understand auction schedules and secondary-market dynamics. For voluntary purchases, prioritize credits that meet ICVCM Core Carbon Principles — additionality, permanence, and third-party verification matter more than price.
5. Track and report. Retire credits properly in recognized registries. Document everything. Explore verified offset projects that match your sector and values, and revisit your strategy annually as state programs evolve.
The US carbon market isn't simple, but it's navigable. Start with your numbers, understand your geography, and build from there.