Free for whom? HOTNAT, reciprocity and competition in European cross-border rail

Railteam, an alliance of European high-speed operators, offers HOTNAT: passengers who miss a cross-border connection may board another member's next available train at no extra charge. The European Commission's May 2026 Passenger Package would extend passenger rights across multi-operator journeys, making HOTNAT's design a live question. Reciprocity saves transaction costs while claims roughly balance, but operators differ in network size, connecting traffic, frequency, reliability and the value of a spare seat. Without settlement, the operator causing a missed connection shifts part of the cost to whoever carries the passenger, weighing most heavily on small point-to-point operators. Attribution suffers too: the passenger meets the operator without a seat, not the one that caused the delay. When authorised passengers outnumber spare seats, no published rule decides who travels. Onward travel should stay free at the point of use. A flat, causation-based clearing tariff with netting and a published priority order would preserve that benefit, spread recovery costs neutrally and sharpen reliability incentives.