There are 16.7% of smokers in Japan. Mostly smoking is not allowed in public areas these days in Japan. Instead, most places have smoking room or places for smokers. You can find smoking rooms that are placed in every each Shinkansen stations through Japan.
I will show you where you can find the smoking rooms while transporting by Shinkansen.

Where you can find smoking rooms

Every station of the Tokaido Shinkansen has a smoking room somewhere. There are two types. One type is smoking room on the Shinkansen platforms, the other type is at the concourse of the Shinkansen (Inside the ticket gate).

Exepting stations, you also can find smoking room in the Shinkansen trains. Only the Tokaido Shinkansen has smoking rooms inside the train.

Smoking rooms at stations

Tokyo station

At Tokyo station you will find smoking rooms on each platforms. There are no smoking rooms around the concourse.

• tracks14,15 … around car no 11
• tracks16,17 … around car no 16
• tracks18,19 … around car no 16

Shinagawa station

Shinagawa station has two rooms at the South concourse and the North concourse. It is opened every time for everybody.

Shin-Yokohama station

Shin-Yokohama station has two room at the West concourse and East concourse.

Odawara station

You can find the only smoking room by the right side of the Shinkansen ticket gate.

Atami station

On the left hand by the Shinkansen ticket gate.

Mishima station

Smoking rooms are on the Shinkansen platforms.

• track 5…around car no 16
• track 6…around car no 16

Shin-Fuji station

On the right hand by the Shinkansen ticket gate.

Shizuoka station

Shizuoka has smoking rooms on the platform. The snap is track number 6.
The smoking room is around car no 16.

Kakegawa station

You can see the smoking room straight ahead from the Shinkansen ticket gate.

Hamamatsu station

Smoking rooms at Hamamatsu station are on the Shinkansen platforms. You will find them around car no 16.

Toyohashi station

On the left hand by the Shinkansen ticket gate. If you use the transfer gate, it will be on your right hand.

Mikawa-Anjo

On the left hand by the Shinkansen ticket gate.

Nagoya station

Nagoya station has smoking rooms on the Shinkansen platforms.

• tracks 14,15…around car no 9
• tracks 16,17…around car no 16

Gifu-Hashima station

Next by the toilet in the concourse.

Maibara station

Next by the toilet in the concourse.

Kyoto station

Kyoto station is the most difficult station to find the smoking room. After you get through the Shinkansen ticket gate, head for “Shinkansen Hatijyo East Exit”. It is next to the waiting room.

Shin-Osaka station

Shin-Osaka station is a huge station but there is only one smoking room. The smoking room is near by the Central ticket gate.
There used to be smoking rooms on each platforms, but was moved near the ticket gate. Better for JR to clean it up.

Smoking rooms in the Shinkansen

The Tokaido Shinkansen has smoking rooms in the train. All over the country, there is no such train witch has a smoking room aboard.

You can find the smoking room at decks at car number 3,10 and 15. Car number 10 is only for passengers who reserved the green car. The Tokaido Shinkansen has 16cars, car number one facing Shin-Osaka (west) and car number sixteen faces Tokyo station (East).

The smoking room in the train is not so wide and because of the Covid-19, only two persons can use it in the same time. So you might have to wait a little.

Conclude

Japans Shinkansen is friendly for smokers. You can smoke while your waiting at stations and also do so in the train while your headed for your destination. Please use the smoking room with good manners.