Most of the network is located in the 23 special wards, with portions extending into Chiba and Saitama Prefectures.

There are two primary subway operators in Tokyo: As of 2023[update], the combined subway network of the Tokyo and Toei metros comprises 286 stations and 13 lines covering a total system length of 304.0 kilometers (188.9 mi).

The Tokyo Metro and Toei networks together carry a combined average of over eight million passengers daily.

However, the separate administration of metro systems has some ramifications: As is common with Japanese subway systems, many above-ground and underground lines in the Greater Tokyo Area operate through services with the Tokyo Metro and Toei lines.

In a broader sense they are considered a part of the Tokyo subway network, allowing it to reach farther out into the suburbs.