Nationally Determined Contributions

A nationally determined contribution (NDC) is each Party's plan for contributing to the Paris Agreement's climate goals, especially through emission reduction and limitation measures. The mechanism combines nationally chosen commitments with common international rules, creating a bottom-up pledge system within a multilateral framework. It applies to every Party while recognizing different national circumstances and capabilities.

The five-year ambition cycle

Under Article 4, every Party must prepare, communicate and maintain successive NDCs, and pursue domestic mitigation measures aimed at achieving them.

• A new NDC must be communicated every five years, and a Party may strengthen its existing contribution at any time.
• Each successive NDC must represent a progression beyond the previous one and reflect the Party's highest possible ambition.
• NDCs are recorded in a public registry maintained by the UNFCCC secretariat.
• Parties must provide information necessary for the clarity, transparency and understanding of their NDCs.

National flexibility and differentiation

Parties determine the content and ambition of their own contributions, but do so in the light of equity and common but differentiated responsibilities and respective capabilities, reflecting different national circumstances.

• Developed countries should continue taking the lead through economy-wide absolute emission reduction targets.
• Developing countries should enhance mitigation efforts and are encouraged to move progressively towards economy-wide targets.
• Implementation by developing countries recognizes the availability of support, including finance, technology transfer and capacity-building.
• An NDC may also communicate adaptation-related priorities, although mitigation commitments form its central Article 4 component.

Transparency and collective review

The mechanism links national action to international scrutiny without internationally assigning each country's target.

• Parties must account for their NDCs using approaches that promote environmental integrity, transparency, accuracy, completeness, comparability and consistency.
• The enhanced transparency framework under Article 13 tracks implementation and progress through national reporting and technical expert review.
• The global stocktake under Article 14, conducted every five years, assesses collective progress and informs subsequent NDCs.
• The Agreement legally binds Parties to procedural duties such as preparing and communicating NDCs, but does not make achievement of each nationally chosen target legally enforceable.