Global Tax Overhaul Gains Steam as G20 Backs New Levies

The approach marks a reversal of years of economic policies that embraced low taxes as a way for countries to attract investment and fuel growth.

VENICE — Global leaders on Saturday agreed to move ahead with what would be the most significant overhaul of the international tax system in decades, with finance ministers from the world’s 20 largest economies backing a proposal that would crack down on tax havens and impose new levies on large, profitable multinational companies. If enacted, the plan could reshape the global economy, altering where corporations choose to operate, who gets to tax them and the incentives that nations offer to lure investment. But major details remain to be worked out ahead of an October deadline to finalize the agreement and resistance is mounting from businesses, which could soon face higher tax bills, as well as from small, but pivotal, low-tax countries such as Ireland, which would see their economic models turned upside down. After spending the weekend huddled in the halls of an ancient Venetian naval shipyard, the top economic officials from the Group of 20 nations agreed to forge ahead. They formally threw their support behind a proposal for a global minimum tax of at least 15 percent that each country would adopt and new rules that would require large global businesses, including technology giants like Amazon and Facebook, to pay taxes in countries where their goods or services are sold, even if they have no physical presence there.