Yes, you can absolutely use a PASMO card (or its variant, the PASMO Passport for tourists) on the entire Tokyo Subway network, including both Tokyo Metro and Toei Subway lines. In 2026, Japan’s IC card system remains fully integrated, meaning you can also use PASMO on JR East trains, private railways, and buses throughout the city. To use it, you simply tap the card against the blue reader at the ticket gates upon entry and exit; the correct fare is automatically deducted from your balance. For those with compatible smartphones, Mobile PASMO can be added to Apple Wallet or Google Pay, allowing you to bypass physical kiosks entirely. While a temporary shortage of physical chips in previous years made some cards harder to find, the "PASMO Passport" is widely available at Narita and Haneda airports specifically for international visitors, offering a convenient, cashless way to navigate the capital's complex transit system.