Tokyo eSIM — plans from ₹299.00

Tokyo has two very different front doors. Haneda (HND) is close to the city, with the Tokyo Monorail to Hamamatsucho and the Keikyu line to Shinagawa; Narita (NRT) is around sixty kilometres out, served by the Narita Express to Tokyo Station and Shinjuku and the Keisei Skyliner to Ueno. Both have vending machines and counters selling prepaid data SIMs in arrivals, and they work, but the machines are frequently sold out at peak hours and the process ends with your home SIM in an envelope. What you actually need first is straightforward: pick the right train, reserve a seat, and add money to a mobile IC card so the ticket gates open. An eSIM installed at home over Wi-Fi is already sitting in the phone for that. It stays inactive until the handset registers on a Japanese network after landing, and only then does validity start, so buying weeks ahead costs nothing.

Japan's networks are NTT Docomo, KDDI au, SoftBank and Rakuten Mobile, and a travel eSIM roams onto the strongest partner signal rather than one carrier. Tokyo has some of the best urban coverage anywhere: 5G is thoroughly deployed across the twenty-three wards, and LTE is fast even in basements and department store levels. The subway is the notable strength — Tokyo Metro and Toei tunnels carry mobile signal, so you stay connected between stations, not just on platforms. Congestion appears at the extremes, such as Shibuya crossing at rush hour. The day-trip belt is well covered too: Hakone, Kamakura, Nikko and the Fuji Five Lakes have service, thinning in mountain valleys. See the Japan plan or Asia.

Download offline maps of central Tokyo and, more importantly, save your hotel's address in Japanese — addresses here are block-based rather than street-based and taxi drivers need the written form. Data is essential for rail routing apps, which are the only sane way to navigate the network, for mobile IC card top-ups, for restaurant reservations and for translating menus by camera. Convenience store and station Wi-Fi exists but is sign-in heavy and slow. Hotspot works on most plans, which suits the many travellers working from Tokyo hotels. Carry a power bank: a day of rail apps, camera and translation is punishing. Check your model on the compatibility page, and see Kyoto if you are going west.