Mitarbeiter sonstige

Domestic revenue mobilisation, the financing gap and why tax expenditures matter

Sen, Kunal / Christian von Haldenwang
Mitarbeiter sonstige (2026)

in: Anna-Katharina Hornidge / Axel Berger (eds.), Disruption and Reform: sustainable futures at stake? The case for politics of cooperation and perseverance, Bonn: German Institute of Development and Sustainability (IDOS), 51-55

ISBN: 978-3-96021-292-8
DOI: https://doi.org/10.23661/r4.2026

As governments increasingly prioritise national interests, security concerns and geopolitical competition over collective global responsibilities, traditional development finance mechanisms are being weakened, repurposed or redirected towards advancing narrow strategic objectives. The Organisation for Economic Co-operation and Development projects a 23 per cent decline in official development assistance (ODA) between 2024 and 2025 (OECD, 2026). This reduction not only has immediate consequences for the lives and livelihood of millions of people in low-income countries (LICs) who depend on external assistance, but also creates uncertainty for partner countries, disrupts long-term development planning, and undermines the legitimacy and effectiveness of development cooperation. At the same time, development finance needs have risen sharply and continue to rise due to the climate crisis, the impacts of the COVID-19 pandemic, supply chain disruptions and rising food and energy prices. Together, these pressures have contributed to a projected USD 6.4 trillion financing gap for achieving the Sustainable Development Goals (SDGs) by 2030 (OECD, 2025a). Against this backdrop, mobilising greater volumes of private capital aligned with the SDGs has become increasingly important (on the need for the European Union to become more adept at facilitating private investment, see the contribution by Keijzer & Furness in this volume). In particular, blended finance has frequently been promoted as one key instrument to achieve this objective (on domestic revenue mobilisation as another key approach, see the contribution by Sen & von Haldenwang in this volume). However, despite growing attention from policy-makers and development institutions, the scale of blended finance has remained well below expectations and so far made only a limited contribution to closing the SDG financing gap. Although transaction volumes increased from USD 11.5 billion in 2020 to USD 18.3 billion in 2024, they remain small relative to the estimated USD 4 trillion annual SDG financing gap (Convergence, 2025; OECD, 2025a). As such, the Sevilla Commitment (UNCTAD, 2025) calls for scaling up private capital mobilisation through blended finance and a broader use of risk-sharing instruments. This chapter discusses the benefits and limits of blended finance as well as reforms that are needed at different levels to scale up blended finance and enhance its development impact.