Governments facing high debt, persistent fiscal deficits and rising spending demands are under increasing pressure to raise revenue without undermining economic growth. Recent International Monetary Fund research points to tax-system design, rather than higher headline rates alone, as a potentially important way to strengthen public finances while preserving incentives to work, save and invest.

Broadening the Tax Base Could Matter More Than Raising Rates

The IMF’s research emphasizes that successful tax reforms often focus on broadening the tax base rather than increasing statutory rates, particularly where existing rates are already relatively high. Reducing unnecessary exemptions, deductions, tax holidays and preferential regimes can bring more economic activity into the tax system without imposing a higher marginal rate on taxpayers who are already compliant.

The scale of the opportunity can be significant. IMF analysis published in 2025 estimates that tax expenditures average about 19.7% of tax revenue in low-income developing countries and 27.7% in emerging-market economies. While some tax incentives serve legitimate economic or social objectives, their accumulation can reduce revenue, complicate administration and create uneven treatment across businesses and households.

Tax Design Can Influence Growth

The issue extends beyond government revenue. IMF research has found that the structure of taxation can influence long-term economic performance by affecting incentives for investment, employment, saving and consumption. In a study covering 30 OECD countries, the IMF found that improving the efficiency of VAT systems through broader coverage and fewer reduced rates and exemptions could be more supportive of long-run growth than simply increasing the standard VAT rate.

This distinction is increasingly relevant as governments attempt to balance fiscal consolidation with economic expansion. A tax system that collects more revenue by reducing distortions may create a different economic impact from one that relies primarily on higher rates.

Administration Is as Important as Tax Policy

Better rules alone may not deliver higher collections if enforcement and administration remain weak. IMF research on tax administration indicates that an improvement in administrative strength from the 40th to the 60th percentile is associated with an increase in tax revenue equivalent to 1.8 percentage points of GDP, although the estimated range is broad.

Digital reporting, improved taxpayer services, stronger compliance systems and better access to third-party data can therefore complement changes to tax policy. The IMF has increasingly framed revenue mobilization as an integrated process involving tax rates, the tax base, legislation and administration rather than as a simple question of how much governments charge.

For global markets, the next phase of tax reform will be closely linked to fiscal sustainability and growth prospects. Governments are likely to face greater pressure to identify revenue opportunities that minimize economic distortions, while investors will continue to monitor how changes to VAT, corporate taxation, property taxes and tax incentives affect corporate costs, household demand and public debt dynamics.