By prefecture

Where we have checked so far. Coverage grows region by region.

Oita

43 onsen · 32 welcome tattoos · 5 open to day visitors

Kanagawa

28 onsen · 17 welcome tattoos · 11 open to day visitors

Hokkaido

23 onsen · 3 welcome tattoos · 17 open to day visitors

Gunma

22 onsen · 7 welcome tattoos · 5 open to day visitors

Hyogo

16 onsen · 6 welcome tattoos · 2 open to day visitors

Wakayama

16 onsen · 1 welcome tattoos · 3 open to day visitors

Tokyo

15 onsen · 7 welcome tattoos · 2 open to day visitors

Kyoto

14 onsen · 2 welcome tattoos · 7 open to day visitors

Osaka

14 onsen · 3 welcome tattoos · 2 open to day visitors

Nagano

11 onsen · 0 welcome tattoos · 1 open to day visitors

Gifu

11 onsen · 0 welcome tattoos · 4 open to day visitors

Shizuoka

11 onsen · 3 welcome tattoos · 2 open to day visitors

Ishikawa

10 onsen · 0 welcome tattoos · 1 open to day visitors

Yamanashi

9 onsen · 2 welcome tattoos · 1 open to day visitors

Niigata

8 onsen · 0 welcome tattoos · 0 open to day visitors

Akita

8 onsen · 0 welcome tattoos · 7 open to day visitors

Aomori

4 onsen · 1 welcome tattoos · 4 open to day visitors

Yamagata

4 onsen · 0 welcome tattoos · 0 open to day visitors

Ehime

4 onsen · 3 welcome tattoos · 1 open to day visitors

Miyagi

3 onsen · 0 welcome tattoos · 1 open to day visitors

Fukushima

3 onsen · 1 welcome tattoos · 1 open to day visitors

Fukui

2 onsen · 0 welcome tattoos · 0 open to day visitors

Iwate

2 onsen · 0 welcome tattoos · 2 open to day visitors

Tokushima

2 onsen · 0 welcome tattoos · 2 open to day visitors

Kagoshima

1 onsen · 0 welcome tattoos · 0 open to day visitors