No, the Shinkansen (Bullet Train) does not run 24/7. In 2026, all Shinkansen lines across Japan maintain a strict "overnight curfew" for maintenance and safety inspections. The first trains typically depart around 6:00 AM, and the final services usually arrive at their destinations by midnight. This 6-hour window (midnight to 6:00 AM) is used by "Doctor Yellow" and other maintenance vehicles to inspect the tracks, ensuring the Shinkansen's incredible 60-year record of zero passenger fatalities due to derailment or collision. Because there are no sleeper bullet trains, if you miss the last train (usually around 9:30 PM for a long-haul trip from Tokyo to Osaka), you are stuck until morning. It is a high-value strategy to use the "Japan Transit" or "Navitime" app to check the "Last Train" (Saishu-densha) for your specific route. For those needing to travel overnight, the only options are the "Sunrise Express" (the last remaining conventional sleeper train) or the much slower overnight "Highway Buses."