South Korea runs a national emissions trading scheme, the K-ETS. It is a market for the country’s biggest emitters, not for individuals, who buy voluntary credits instead. This guide explains how the K-ETS works, what changed in its fourth phase, and the rules on claims. For other countries, see our countries hub.
South Korea’s compliance market (K-ETS)
The K-ETS rests on the Act on the Allocation and Trading of Greenhouse-Gas Emission Permits of 2012Source 5, and it has run since 1 January 2015Source 7. It covers businesses whose average emissions over the previous three years are at least 125,000 tCO₂e, or that have a site emitting at least 25,000 tCO₂eSource 5. The government says the K-ETS covers 70% or more of national greenhouse gas emissionsSource 4.
Scrolls sideways to show every column.
| Item | Detail |
|---|---|
| Total cap | 2.5373 billion tonnes over 2026–2030 |
| Market Stability Reserve | Newly included within the total cap |
| Power sector auctioning | Paid allocation rising to 50% by 2030 |
| Offsets | Up to 5% of each entity’s compliance obligation |
As of Oct 2026
The cabinet approved the Phase 4 allocation plan on 11 November 2025, with the cap, reserve and auctioning figures aboveSource 6. The offset limit for Phase 4 is reported by ICAPSource 7.
South Korea’s 2030 NDC aims to cut national greenhouse gas emissions by 40% from 2018 levels, and its 2035 NDC sets a 53–61% cut in net emissions from 2018 levelsSource 4.
How allowances trade
Anyone who wants to trade emission permits must register an account in the emission permits registerSource 5. The Greenhouse Gas Inventory and Research Center (GIR) runs the registry systems for allowances and offsetsSource 9. Allowances trade on the Korea Exchange, where trades settle on the day of trading and GIR transfers the permits from the seller’s registry accountSource 8.
Offsets inside the K-ETS
A covered business that holds reductions from an external project meeting international standards can ask the authority to convert them into emission permitsSource 5. In Phase 4, ICAP reports that international credits used this way must comply with Article 6 of the Paris AgreementSource 7. This is a compliance route for covered companies. Our guide to voluntary vs compliance markets explains the difference.
Buying voluntary credits in South Korea
If you are not a covered company, you buy voluntary credits from online retailers, marketplaces and brokers, usually from international projects. Compare providers on registry serials and certificates in where to buy.
Before you pay, ask which registry holds the credits and check that they are retired in your name.
If you buy for a company, decide first what you want the credits to do. Credits bought to compensate voluntarily for emissions are different from offsets a covered company converts into permits for K-ETS compliance, and the two follow different rules. Keep the retirement records with your emissions inventory, so anyone checking your claims can trace each tonne. Our guide for companies covers sizing, contracts and due diligence.
Reduce first, then offset
Cut what you can before you buy, and use credits for the emissions that are left. Our guide for individuals shows how to size a purchase.
Claims and tax notes
What you can say about offsets
The Act on Fair Labeling and Advertising aims to prevent labels and advertisements that deceive or mislead consumers, and treats concealing or whitewashing any fact in an advertisement as deceptiveSource 12. Facts stated in a label or advertisement must be verifiable, and the Korea Fair Trade Commission can ask the business for supporting materialSource 12. Its guidelines on labelling and advertising of environmental facts apply these rules to environmental claimsSource 12.
Whatever label you use, the evidence that matters is the same: which credits were retired, how many, and where the registry record is. Ask for it before you rely on a claim, and give it when you make one.
On tax, we found no National Tax Service guidance in English on VAT or income tax for buying carbon credits or allowances. Get professional advice before you buy in volume.
How to check quality before you buy
Each Verra credit represents one tonne of CO₂e reduced or removedSource 1, and registries such as Gold Standard’s track every credit from issuance to retirementSource 2. That makes three checks possible before you pay:
- Is it in a public registry? Ask for the registry and serial numbers, and check the credits are retired in your name.
- Is the method credible? The ICVCM’s Core Carbon Principles set a quality threshold, and credits that meet it can carry the CCP labelSource 3.
- Is the seller clear? A good seller says what you are buying, what it charges and how and in whose name it retires credits.
Our guide to how to verify carbon credits shows the steps, and carbon credit scams lists the warning signs.
Article 6 deals
South Korea’s carbon neutrality law sets the legal basis for international mitigation cooperation under Article 6 of the Paris AgreementSource 10, and its 2035 NDC says it intends to use voluntary cooperation under Article 6Source 4. In 2023 the environment ministry listed agreements already signed with Vietnam and Mongolia for sector-specific projectsSource 11.
Japan cooperates with partner countries through its own bilateral mechanism; see our Japan guide. For Singapore’s Implementation Agreements, see Singapore.
How to buy, step by step
Step 1: Work out what to cover
Estimate your footprint and cut what you can first.
Step 2: Choose a project type
Pick credits from a standard and project type you trust.
Step 3: Pick a provider
Compare retailers, marketplaces and brokers on registry serials and certificates.
Step 4: Check the registry record
Confirm the credits are retired in your name on the registry.