Meaningful Action Built on Sound Evidence and Shared Expertise.

The Global Solidarity Levies Task Force conducts cutting-edge consultations and research studies to build the political will and technical expertise necessary for implementing effective solidarity levies.

By bringing together specialists from academia, business, civil society, and government—representing both the Global North and South—we ensure our recommendations are credible, balanced, and grounded in real-world implementation challenges.

Our Flagship Reports:

The Untapped Potential of Solidarity Levies: Recommendations for the Future of Climate and Development Finance

November 2025, COP30

This report provides a comprehensive overview of the leading options for solidarity levies: policies with significant potential to unleash billions in new, debt-free climate and development finance for developing countries.

From Seville to Belém: A Roadmap for Solidarity Levies from FFD4 to COP30

June 2025, FFD4

This report provides a status update of the task force as of the 4th International Conference on Financing for Development (FFD4), which took place in Sevilla in June 2025. The report outlines an overview of the work and progress made by the task force since COP29, the sectors they are focusing on implementing solidarity levies, and next steps ahead of COP30.

Scaling Solidarity: Progress on Global Solidarity Levies

November 2024, COP29

This progress report unveils more specific policy options for levies that the task force has investigated since its inception: fossil fuels, aviation, maritime fuel, carbon pricing and financial transactions. It also identifies three additional policy areas for further research, which have significant potential to raise finance equitably while reducing emissions and pollution: a cryptocurrency levy, an ultra-high-net-worth individual tax, and a plastics production levy.

In-Depth Research Papers:

Levies on Premium Flyers: Legal Handbook

November 2025

The Legal Handbook distills comparative experience with aviation taxation from national practices, international legal frameworks, and recent climate-related fiscal innovations. Together, these elements provide a pathway for governments to reach consensus at COP30 and translate commitment into action with the Premium Flyers Solidarity Levy Coalition.

Preview: Impact of Premium Flyer Levies in SIDs and LDCs 

November 2025

This study assesses the potential of a Premium Flyers Solidarity Levy as an equitable and predictable source of climate finance, in particular for Small Island Developing States (SIDS) and Least Developed Countries (LDCs). Building on the principles of “polluter pays” and “ability to pay,” the proposed levy targets first- and business-class passengers, representing high-emission, high-income travel segments, to generate dedicated adaptation revenues without significantly affecting demand. The study has been undertaken by Prof. Mizan Khan, Ayesha Noor & Ekhtekharul Islam, and the full publication is forthcoming in 2026.

Towards a Crypto Solidarity Levy

November 2025

The Global Solidarity Levy Task Force set up an International Expert Commission on Crypto Asset Levies for Climate & Development (expert commission). The question which the Task Force has set out to explore through this expert group is whether a levy imposed on the crypto ecosystem could be devised with the purpose of promoting climate, fiscal justice, and/or development.

Taxing Polluters: What is the Impact of a Global Minimum Tax on the Extractive Sector

September 2025

This new report commissioned by the Global Solidarity Levies Task Force, assesses the potential and limitations of applying the OECD / G20 global minimum tax (Pillar Two) to the extractive sector, a high-profit and high-emission industry at the center of climate and development debates.

A Practical Negotiation Framework to Finance the Low Carbon Transition and Development

June 2025

This article argues that it is still possible to make meaningful climate and development progress by designing targeted global solidarity levies. This article first proposes a structured theoretical framework and process for practical negotiations to form a climate club, with a focus on the aviation sector. It then presents the early-release of a robust quantitative tool—a technical simulator of the levy’s operation—to allow participants to evaluate potential revenue outcomes, sensitivity to policy parameters, and fair redistribution mechanisms.

A Fair Share from Aviation

June 2025

At the request of the Task Force, CE Delft conducted an impact assessment of the aviation levies, currently under development by the Task Force. The levies are assessed in different regimes (rates, geographical scope).

The Case for a Green Financial Transaction Tax

November 2025

The aim of this note is to assess whether and how the Financial Transaction Tax (FTT) could be “greened” – that is, adapted or utilized to support environmental objectives and the financing of the transition to a more sustainable economy. While traditionally conceived as a regulatory tool, the FTT also holds unexploited potential as an instrument for climate finance and broader environmental alignment.

Levies on Equity Transactions to Finance Climate Action

June 2025

Financial Transactions Taxes (FTTs) on equity trading, already implemented in several countries and generating around $17 billion annually, represent an underutilised but promising revenue stream for climate development and action. The study highlights the FTT as a technically feasible, low-cost, and non-distortive mechanism to raise climate finance quickly and effectively, fulfilling the criteria sought by Task Force and offering a practical path forward in the broader effort to scale up international development and climate funding.

Global Financial Architecture Reform and Solidarity Levies 

February 2025

This brochure provides a brief overview of solidarity levies and how they can help fund climate and development.