Tax comparisons are only as useful as the definitions behind them. Two countries can appear to have similar tax levels while looking completely different to the average worker — because one relies on consumption taxes and the other on labour taxes. One measures the tax burden on the whole economy as a share of GDP. Another measures what a specific average worker actually loses before their pay arrives. Both are important. Neither is sufficient alone.
OECD — Revenue Statistics 2025 (PRIMARY · oecd.org · doi.org/10.1787/3a264267-en · December 9, 2025 · OECD Publishing)
45.2%
“Across OECD countries, tax-to-GDP ratios ranged from 18.3% in Mexico to 45.2% in Denmark in 2024. Between 2023 and 2024, the OECD average tax-to-GDP ratio increased from 33.7% to 34.1%. This was the first annual increase since 2021.” — OECD Revenue Statistics 2025 primary verbatim.
Denmark’s 45.2% tax-to-GDP ratio in 2024 was the highest in the OECD “for the second consecutive year.” France was second at 43.5%, Austria third at 43.4%. Eight countries sat above 40%: alongside the three leaders, Finland, Belgium, Sweden, Norway, and Italy all cleared the threshold. The 27-point gap between Denmark’s 45.2% and Mexico’s 18.3% is one of the widest in the club of rich democracies. The OECD’s Revenue Statistics 2025, published December 9, 2025, confirms the 2024 increase was the first since 2021. Latvia saw the sharpest 2024 rise at +2.4 percentage points, driven by higher revenues from personal income tax, social security contributions, and corporate income tax. Slovenia rose +1.9pp. Colombia saw the sharpest decline at -2.2pp. In 22 of 36 countries where preliminary 2024 data was available, tax ratios rose year-on-year. The historical trend underlying the 2024 snapshot is even more significant: “Between 1965 and 2023, the average tax-to-GDP ratio among OECD countries increased from 24.9% to 33.7%, an increase of 8.9 percentage points.”
Source: OECD — Revenue Statistics 2025: Disentangling Personal Income Tax Revenue in OECD Countries (PRIMARY · doi.org/10.1787/3a264267-en · December 9, 2025 · OECD Publishing · KEY VERBATIM: “Denmark had the highest tax-to-GDP ratio among OECD countries for the second consecutive year in 2024, at 45.2%” · “France had the second-highest tax-to-GDP ratio in 2024 (43.5%) followed by Austria (43.4%)” · “Mexico had the lowest” at 18.3% · “Six other countries had tax-to-GDP ratios above 40%: Finland, Austria, Belgium, Sweden, Norway and Italy” · “Across OECD countries, tax-to-GDP ratios ranged from 18.3% in Mexico to 45.2% in Denmark in 2024” · “Between 2023 and 2024, the OECD average tax-to-GDP ratio increased from 33.7% to 34.1%” · “This was the first annual increase since 2021” · “In 2024, tax-to-GDP ratios increased from the previous year in 22 of the 36 countries for which preliminary data is available, declined in 13 countries and remained unchanged in one” · “The largest increase in 2024 was observed in Latvia, whose tax-to-GDP ratio rose by 2.4 p.p. due to higher revenues as a share of GDP from personal income tax (PIT), social security contributions and corporate income tax (CIT)” · “The second-largest increase was in Slovenia, where tax revenues rose by 1.9 p.p.” · “The largest decline in the tax-to-GDP ratio in 2024 occurred in Colombia, of 2.2 p.p.” · “Between 1965 and 2023, the average tax-to-GDP ratio among OECD countries increased from 24.9% to 33.7%, an increase of 8.9 p.p.”)
“In 2024, the largest tax wedge for this household type was observed in Belgium (52.6%), Germany (47.9%), France (47.2%), Italy (47.1%) and Austria (47.0%).”
— OECD — Taxing Wages 2025 (PRIMARY · oecd.org · doi.org/10.1787/b3a95829-en · April 30, 2025 · 2024 data · single worker, average wage, no children)
Why Nordic Countries Dominate the Top — and Why Ireland Sits at the Bottom
Denmark’s 45.2% does not come primarily from high income tax rates. It comes from a specific design choice: Denmark finances its welfare state more through individual income taxes than through social security contributions, unlike France, Germany, or Belgium. Danes pay high income taxes directly and in return receive free university education, universal healthcare, generous unemployment benefits, and one of the world’s best-funded eldercare systems. Ireland at 21.3% sits near the bottom of the OECD. This is not because Ireland has a small welfare state — it is because Ireland has an unusual tax mix, reliant on corporate income tax revenues from multinationals rather than high personal or consumption taxes. The same tax-to-GDP ratio can represent a social democratic welfare state (Denmark) or a liberal low-regulation model (Ireland), depending on what the revenue funds and how it is collected.
Why it matters: high tax-to-GDP ratios are not inherently good or bad. They reflect choices about what governments provide. Denmark’s 45.2% funds a social contract that includes free university education, universal healthcare, world-class parental leave, and active labour market programmes. These services cost money. The question is not whether 45.2% is too much or too little — it is whether the services provided are worth what is collected.
OECD — Taxing Wages 2025 (PRIMARY · doi.org/10.1787/b3a95829-en · April 30, 2025 · 2024 data) + OECD — Taxing Wages 2026 (PRIMARY · oecd.org · 2025 data · FRESHEST)
52.6%
Belgium’s tax wedge in 2024 — the share of total labour costs absorbed by income taxes and social security contributions. “In the case of a single worker earning the average wage (AW), the tax wedge ranged from zero (Colombia) and 7.2% (Chile) to 47.9% (Germany) and 52.6% (Belgium).” — OECD Taxing Wages 2025 primary verbatim. 2025: Belgium 52.5%, still #1 (Taxing Wages 2026, freshest).
The tax wedge is the metric that matters most to employers making hiring decisions and workers evaluating job offers. Belgium’s 52.6% in 2024 means that of every €100 an employer spends on labour, only €47.40 reaches the worker after all income taxes and social security contributions on both sides are deducted. Belgium’s personal average tax rate — income tax alone, as a share of gross wages — was 39.7% in 2024, the highest in the OECD. “Denmark, Germany, Lithuania and Slovenia were the only other countries with rates above 35%.” Belgium’s marginal tax rate for the average worker was 55.6% in 2024 — “higher than 55% only in Belgium” across the entire OECD. France had the highest employer social security contributions at 26.7% of labour costs — “the highest amongst OECD countries” (OECD Taxing Wages 2025 verbatim) — and this is why France’s tax wedge (47.2%) approaches Germany and Italy despite France having a lower total tax-to-GDP ratio than some Nordic countries. The OECD average tax wedge was 34.9% in 2024 and rose to 35.1% in 2025 (Taxing Wages 2026). In 2025, nine countries saw their tax wedge decline: Australia, Denmark, Iceland, Ireland, Italy, Latvia, Portugal, Sweden, and the United States.
Source: OECD — Taxing Wages 2025 (PRIMARY · doi.org/10.1787/b3a95829-en · April 30, 2025 · KEY VERBATIM: “In 2024, the largest tax wedge for this household type was observed in Belgium (52.6%), Germany (47.9%), France (47.2%), Italy (47.1%) and Austria (47.0%)” · “The tax wedge of a single worker with no children earning the average national wage was 34.9% of labour costs on average across the OECD in 2024” · “In the case of a single worker earning the average wage (AW), the tax wedge ranged from zero (Colombia) and 7.2% (Chile) to 47.9% (Germany) and 52.6% (Belgium)” · “Belgium had the highest rate [personal average tax], at 39.7%; Denmark, Germany, Lithuania and Slovenia were the only other countries with rates above 35%” · “The personal average tax rate for this household type was 25.0% of gross wage earnings in 2024” · “The marginal tax rate for the average worker was higher than 55% only in Belgium (55.6%)” · “Employers in France paid 26.7% of labour costs in SSCs, the highest amongst OECD countries”) + OECD — Taxing Wages 2026 (PRIMARY · oecd.org/en/publications/taxing-wages-2026_3a5169ef-en · 2025 data · FRESHEST · KEY VERBATIM: “The largest tax wedge was observed in Belgium (52.5%) and the lowest in Colombia (0.0%)” · “the average tax wedge as a percentage of labour costs in OECD countries was 35.1% in 2025”)
The 60-Year Rise — 24.9% in 1965 to 34.1% Today
The long-run OECD average tells a story of slow, sustained growth in the state’s share of the economy. In 1965, the average OECD country collected taxes equivalent to 24.9% of GDP. By 2023, that had risen to 33.7% — an increase of 8.9 percentage points over 58 years. In 2024, it ticked up again to 34.1%, the first increase since 2021. The direction has been consistent: more taxes, not fewer. The reasons are structural. Ageing populations require more spending on pensions and healthcare. Welfare states expanded after World War II and their costs have grown with demographics. Public debt servicing costs have risen as debt levels increased. And the COVID-19 pandemic’s fiscal legacy — emergency spending financed by borrowing — has created pressure to raise revenues in the years since. The 2024 increase, with 22 of 36 countries raising their ratios, suggests this structural pressure is back after two years of post-COVID correction.
Why it matters: the OECD average rising from 24.9% to 34.1% in six decades is not primarily a story of tax grabs. It is a story of expanding social contracts — healthcare systems, pension systems, disability support, and education — that required more revenue as populations aged and expectations rose. The question for the next 60 years is whether rising spending pressures (climate adaptation, defence, AI transition, demographic ageing) will push that average toward 40%, and what the political economy of that shift looks like country by country.
OECD — Revenue Statistics 2025 (PRIMARY · December 9, 2025) · OECD — Taxing Wages 2026 (PRIMARY · 2025 data · freshest) · Eurostat (PRIMARY · April 22, 2026)
8.9pp
“Between 1965 and 2023, the average tax-to-GDP ratio among OECD countries increased from 24.9% to 33.7%, an increase of 8.9 p.p.” — OECD Revenue Statistics 2025 primary verbatim. In 2024, the average rose further to 34.1%, the first annual increase since 2021, as 22 of 36 countries raised their tax ratios. For individual workers, the OECD average tax wedge reached 35.1% in 2025 (Taxing Wages 2026, freshest).
The OECD’s “special feature on disentangling personal income tax revenue” in Revenue Statistics 2025 highlights another dimension of the long-run trend: not just how much governments collect, but what they collect it through. Since 1965, income taxes have risen as a share of total revenues, while some commodity-linked revenues (particularly in resource-rich countries) have been volatile. The 2024 snapshot also reveals a nuance: Latvia’s +2.4pp was the largest single-country increase in 2024, driven by deliberate policy decisions to raise PIT, SSC, and CIT revenues simultaneously — a rare case of intentional across-the-board revenue increases rather than automatic fiscal drag. Colombia’s -2.2pp was the sharpest decline, driven by a fall in corporate income tax revenues. The European Union average (including social contributions) reached 40.4% of GDP in 2024, significantly above the OECD average, reflecting the density of high-tax welfare states within the EU. Ireland stands out as the lowest EU member at 22.4% — a stark reminder that the EU average conceals enormous variation, from Denmark’s 45.8% (Eurostat, including SSC) to Ireland’s 22.4%.
Source: OECD — Revenue Statistics 2025 (PRIMARY · doi.org/10.1787/3a264267-en · December 9, 2025 · KEY VERBATIM: “Between 1965 and 2023, the average tax-to-GDP ratio among OECD countries increased from 24.9% to 33.7%, an increase of 8.9 p.p.”) · OECD — Taxing Wages 2026 (PRIMARY · oecd.org · 2025 data · freshest · Belgium 52.5% still #1 · OECD average 35.1% in 2025) · Eurostat — Tax Revenue Statistics (PRIMARY · ec.europa.eu/eurostat/statistics-explained · updated April 22, 2026 · EU 2024 final data including social contributions · Denmark 45.8% · France 45.3% · Belgium 45.1% · Austria 43.8% · Luxembourg 42.7% · Italy 42.6% · Sweden 42.5% · Finland 42.3% · EU average 40.4% · Ireland 22.4% lowest EU)