Eurostar is an international high-speed rail service connecting the United Kingdom with France, Belgium and the Netherlands. Most Eurostar trains travel through the Channel Tunnel between the United Kingdom and France, owned and operated separately by Getlink.

The London terminus is London St Pancras International; the other British calling points are Ebbsfleet International and Ashford International in Kent. Intermediate calling points in France are Calais-Fréthun and Lille-Europe. Trains to Paris terminate at Gare du Nord. Trains to Belgium and the Netherlands serve Brussels-South and Rotterdam Centraal, before terminating at Amsterdam Centraal. Additionally, in France there are direct services from London to Marne-la-Vallée–Chessy (Disneyland Paris) and seasonal direct services to southern France (Lyon, Avignon and Marseille) in summer, and to the French Alps in winter.

The service is operated by 11 Class 373/1 trainsets, each with 18 coaches, and 17 Class 374 trainsets, each with 16 coaches. The trains run up to 320 kilometres per hour (199 mph) on high-speed lines. The LGV Nord high-speed line in France opened before Eurostar services began in 1994, and newer lines enabling faster journeys were added later: HSL 1 in Belgium and High Speed 1 in southeast England. The French and Belgian parts of the network are shared with Paris–Brussels Thalys services and TGV trains.

Eurostar is operated by Eurostar International Limited (EIL), jointly owned by SNCF, the national railway of France (55%), investment firms (40%), and the National Railway Company of Belgium (5%).