Onome Amuge
With the G20 Summit set to convene in Johannesburg on November 22–23, 2025, policymakers are sharpening focus on the world’s deepening sustainable development financing gap, which has ballooned to an estimated $4 trillion annually. Africa alone accounts for $1.7 trillion, which is more than 40 per cent of the global shortfall.
The widening gap, up from $2.5 trillion in 2015, has emerged as one of the greatest obstacles to advancing the UN’s 2030 Sustainable Development Goals (SDGs). A new global financing plan, drawn up under South Africa’s G20 presidency, is now seeking to restore momentum by placing domestic resource mobilisation (DRM) at the heart of the agenda.
The African Tax Administration Forum (ATAF), a key advocate of stronger DRM measures, argues that the ability of African governments to mobilise tax revenues is essential not only to reduce reliance on volatile external flows but also to reclaim fiscal policy independence.
“Revisiting and refocusing on domestic resource mobilisation is a major component in the basket of funding options required to achieve the SDGs,” ATAF said in a recent publication, welcoming the G20 Development Working Group’s (DWG) acknowledgment of the issue.
At present, Africa’s tax-to-GDP ratio remains below the 15 per cent benchmark considered necessary for sustainable development. Yet even a rise of one percentage point could yield an additional $35 billion annually, amounting to $350 billion by 2030.
One of the largest obstacles to DRM is the persistence of illicit financial flows (IFFs), which siphon billions of dollars from African economies each year through mechanisms such as trade mis-invoicing, transfer mispricing, and tax evasion.
ATAF has urged governments and multilateral partners to embrace a strategic approach, ranging from reforms in tax and trade policies to stronger customs and tax administration. Expanding the tax base, often concentrated on a narrow pool of formal enterprises, remains another priority.
To reinforce cross-border cooperation, ATAF recommends the adoption of unique taxpayer identifiers, the expansion of automatic exchange of tax and customs information, and anti-corruption safeguards. The South African presidency has made IFFs a central theme of its term, securing G20-level backing for the drafting of voluntary, non-binding high-level principles to combat the practice.
The renewed emphasis on DRM comes amid shrinking official development assistance (ODA), tightening global credit conditions, and the rising costs of debt servicing across much of Africa. Together, these trends have constrained fiscal space and left governments vulnerable to external shocks.
Development experts argue that broadening domestic tax revenues offers the most reliable and sustainable route to funding SDG-related investments in health, education, and infrastructure. But reforms will require careful design to ensure inclusivity. ATAF highlights gender-sensitive taxation and policies that empower women as vital elements of effective DRM reforms capable of supporting long-term, equitable growth.
As host of this year’s summit, South Africa is expected to press for an ambitious roadmap on financing for development, aligning the G20’s economic agenda more closely with global development priorities. The summit will also revisit commitments made at the Fourth International Conference on Financing for Development (FFD4), where DRM was first flagged as a cornerstone of funding strategies.
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