In Japan, there is a company known as Tokyo Metro. This is the company that operates the subway system in Tokyo. JR East, on the other hand, operates much of the above-ground railroad system in the Tokyo area and much of the railroad system east of Honshu, including the Shinkansen line.

The primary difference between JR (Japan Railways) lines and Metro lines in Japan is ownership and scope. JR is a group of private companies that descended from the nationalized railway system; they operate the high-speed Shinkansen (bullet trains) and extensive suburban lines like the iconic Yamanote Loop in Tokyo. In contrast, Metro lines (like Tokyo Metro or Toei Subway) are typically city-run or private underground systems designed for dense, inner-city travel. Visually, JR trains often run above ground on elevated tracks, while Metro trains are primarily subterranean. For the 2026 traveler, the distinction matters for ticketing: the JR Pass is generally valid only on JR lines, while city-specific "Metro Passes" only work on subways. However, with a "tap-and-go" IC card like Suica or Pasmo, you can move seamlessly between both systems without needing to worry about the different companies, as the card automatically calculates the correct fare for your entire journey.