In 2026, the cost of a train ticket from Naples to Rome varies significantly based on speed and booking time. For the high-speed Frecciarossa or Italo trains, which whisk you between the cities in just 70 minutes, "Economy" or "Smart" fares typically start around €14.90 to €19.90 if booked several weeks in advance. However, last-minute tickets on these premium lines often climb to €50 or €60. If you are on a budget, the Regionale trains are a flat rate of approximately €13.10, though the journey takes nearly three hours. For travelers in 2026, the "sweet spot" is often the Intercity train, which costs about €27 and takes two hours. To get the best value, it is essential to use the Trenitalia or Italo apps at least 21 days before travel, as 2026 pricing models have become increasingly "dynamic," similar to airline fares, with prices spiking during peak morning and evening commuter hours.