Original Medicare’s usual rule
Care in another country is generally not covered. Medicare.gov describes limited exceptions — for example certain situations in Canada or Mexico when a foreign hospital is closer in an emergency, or when a U.S. hospital is not available. Those exceptions are narrow. Confirm on Medicare.gov before you travel. This is not travel insurance.
Medigap foreign-travel emergency
Some standardized letters (including Plan G and Plan N) include a foreign-travel emergency benefit with limits, a deductible, and a lifetime cap. Read the outline of coverage. It is not worldwide health insurance.
Medicare Advantage
Networks are usually local. Emergency and urgent coverage outside the service area, including abroad, varies by plan. Do not assume last year’s extra benefit still exists. Read this year’s Evidence of Coverage.