Yes, you can take dogs on trains in most parts of the world, but the rules vary significantly by region and size of the dog. In the UK and Europe, trains are exceptionally dog-friendly; most operators allow up to two dogs for free if they are on a lead or in a carrier. Large dogs usually require a muzzle and a half-fare ticket in countries like France or Italy. In the United States, Amtrak's pet policy is more restricted: only small dogs and cats (up to 20 lbs including the carrier) are permitted on most routes for a fee (usually $29–$39), and they must remain in their carrier at all times under the seat. Service animals, however, are always permitted free of charge across all rail systems globally. In 2026, many European "high-speed" lines have dedicated "pet zones" to ensure the comfort of both pet owners and allergic passengers. Always check your specific carrier's website before travel, as some "long-haul" or "sleeper" services may have stricter bans on larger non-service animals.