List of locomotive builders

This list of locomotive builders (companies, government agencies and railways) is ordered by country and includes both modern-day and defunct builders. Since many entities changed their names over time, the most recognisable name is used – generally the one used for the longest time or during the entity's best-known period.

Note: Two factors affect this list's reliability: the preponderance of unreferenced entries and the inconsistency in frequency and coverage of updates.