Riding the bullet train is a great way to get around the country; often times much faster than going to the airport and the hassle of having to go through all the security. There is no check-in process for riding the trains, so you just go the station and find the platform where your train is leaving.
This section gives you some advice on using the bullet trains, known as the "Shinkansen"
Q: Do you need seat reservations?
A: Some trains like the Kagayaki that goes to Kanazawa, or the Hayabusa train that goes to Hakodate, Hokkaido require a seat assignment prior to boarding. The New Year Holidays, the Golden Week Holiday period in May, and the O-bon period in mid-August is when trains tend to get full. Reservations open a month before.
At other times, there usually isn't too big of a concern about all the seats selling out. If you are traveling along the main route between Tokyo and Kyoto/Shin-Osaka, services are so frequent to the point where there are departures every 10 minutes during the peak hours. Most locals just get a ticket from the automated ticket machines (English option available) when they arrive at the station. While the machines accept credit cards, I have noticed that international credit cards get rejected at a very high rate. In that case, you'll have to line up at the ticket office which can take a few minutes. Like in many other places in Japan, it probably is a good idea to be carrying around some cash with you.
Most trains have a few cars which are designated as non-reserved. You simply find a open seat after you get on the train. On the Nozomi trains, this is car 1, 2 and 3. If you are heading to Kyoto, chances are very slim that any of the non-reserved seats will still be vacant when the train arrives at Shinagawa or Shin-Yokohama, so make sure to get a seat assignment before boarding. If your departure point is Tokyo, you have more chances of finding seats for the non-reserved cars.
For the slower Kodama series train, almost the entire train is designated as non-reserved cars. Unless you are traveling in a big group, there is really no need in getting seat assignments as there will always be a seat available somewhere.
The reserved seat cars are for the use of passengers with advance seat assignments. Even when there are open seats, you are not allowed to sit in them if you don't have reservations.
Q: Are there any online booking available?
A: Japanese train operators are quite far behind when it comes to making online purchases. At the moment, JR East has online platforms for its northbound trains (Destination Niigata, Sendai, Yamagata, Akita and Shin-Aomori) and also on the Hokuriku Shinkansen (Nagano, Toyama and Kanazawa) which it runs in conjunction with JR West.
You cannot make a purchase for the Tokaido Shinkansen (Tokyo-Kyoto/Shin-Osaka) as it is run by a different sector JR Central, which has been slow in adopting online bookings. Their trains run very frequently, so most of the time you can visit the ticket office after your arrival and find no problems in getting the tickets you need.
Q: Can luggage be brought on-board?
A: There is space above the seats to put suitcases or backpacks. However it is only suitable for objects that are carry-in size in aircraft. If you have larger suitcases, it might be difficult to find space to store them. One possible solution is to try to make use of the space behind the final row of the train. Always ask for permission from the person sitting on the last row, as putting luggage may obstruct the passenger from reclining the seat.
Most of the northbound trains run by JR East have luggage space at either ends of the car and with the increase of international tourists, there are plans to install more in the coming future. For now, it is advised to be travelling light; otherwise make use of the Takuhaibin (luggage forwarding service) that many hotels can arrange for a fee in order to avoid bringing in large objects to the trains.
Q: What are the facilities on-board the train?
A: All seats have a tray and a pocket to put drinks and belongings. Many of the newer trains have power sockets (100V) on the window-side seats for recharging mobile phones Some the older trains running in the Hikari or Kodama service only have sockets at the very front and back of each car.
Free Wi-fi service has started in a few of the trains, is should be more widely available by 2020, in time for the Olympics.
It is ok to eat and drink in your seat, and most trains have a staff who will sell snacks and beverages, but many people buy something at the station prior to boarding. There is a rubbish bin near the exit of the train and also on the platform.
The Nozomi trains have a small smoking room in a few sections of the 16-car long train. Unbelievably, a few of the older trains in the Hikari and Kodama service running between Tokyo and Hakata still has a smoking car. Fortunately these trains will be put out of service by the spring of 2020. All other trains are completely non-smoking.