US President Donald Trump has threatened an additional 10% tariff on a group of European countries to press a dispute over Greenland. Although Portugal is not a direct target, Portuguese firms face significant indirect impacts via disrupted supply chains, higher input costs, trade diversion and knock‑on retaliatory measures from trading partners. Exporters, import‑dependent manufacturers, logistics firms and financial services are most exposed, with risks including margin compression, price rises for consumers and reduced investment confidence. Businesses and policymakers should prioritise scenario planning, supply chain diversification, targeted support for vulnerable sectors and coordinated diplomatic engagement to limit economic fallout.