No, the London Underground (the Tube) is not included in the Eurail or Interrail pass. Eurail passes are designed for travel on national and international rail networks, not urban municipal transit systems like subways or metros. If you are using your Eurail pass to arrive in London via the Eurostar (at St. Pancras International), you will still need to pay separately for any journeys on the Tube, London Buses, or the DLR. To pay for the Tube in 2026, the most convenient method is using contactless payment (via your credit card or smartphone) or an Oyster Card; both systems automatically calculate the best daily fare "cap" for you. However, there is one small exception in London: the Eurail pass is valid on the Elizabeth Line and the London Overground for specific journeys that connect to the national rail network, but it is rarely worth "using" a travel day on your pass just for a short cross-city trip. Generally, you should keep your Eurail pass for long-distance travel across the UK (on operators like LNER or Avanti West Coast) and use a standard contactless card for all your inner-city London transportation needs.