No, you cannot ride the Narita Express (N'EX) without a seat reservation, as it is an all-reserved seat train. Every passenger must have both a "Basic Fare" ticket and a "Limited Express" reserved seat ticket before boarding. There are no "non-reserved" cars or standing-room areas allowed. If you are using a Japan Rail Pass or a JR East Pass, you must visit a Reserved Seat Ticket Vending Machine (which now include passport readers in 2026) or a JR Travel Service Center to secure a specific seat assignment at no extra cost. For those without a pass, you can purchase a "Reserved Seat Ticket" at the station or via the "JR-EAST Train Reservation" website. If you accidentally board without a reservation, you will be required to pay a surcharge to the conductor, and you will be forced to move or stand if someone with a valid reservation for that seat arrives. To avoid the stress of a "seat hunt" after a long flight, it is best to book your seat as soon as you clear customs at Narita Airport.