Tehran-Esfahan (all trains), Tehran-Shiraz (all trains), Tehran-Mashad (Pardis and quality overnight trains), all trains to Mashad from other cities: at least 2 weeks before departure
Tehran-Yazd (Pardis): at least 1 week before departure
Tehran-Tabriz, Tehran-Ahvaz, Tehran-Kerman, Tehran-Bandar Abbas, Tehran-Zanjan: 4-5 days before departure