Yes, Eurostar tickets frequently sell out, especially during peak travel periods like the summer holidays, Christmas, and major sporting events. In 2026, Eurostar typically releases tickets 6 to 8 months in advance, and the cheapest fares—often starting around €29 to €44—are snapped up almost immediately. As the travel date approaches and seats become limited, prices rise significantly. On popular routes like London to Paris or Brussels to Amsterdam, it is common for all standard and "Plus" class seats to be fully booked several days before departure, particularly on Friday evenings and Sunday afternoons. If a train is sold out, you can occasionally find "Snap" tickets for last-minute travel at a discount, but these are not guaranteed. For 2026 summer travel (mid-May to September), Eurostar advises being "at the front of the digital queue" the moment sales open to ensure both seat availability and the lowest possible "flexible" fares for your itinerary.