Onsen with an open-air bath in Tokyo
Rotenburo — bathing outdoors, which is what most people picture when they picture an onsen.
Times Spa RESTA
タイムズ スパ・レスタ
Tattoos not allowed (day visit)
Spa LaQua
スパ ラクーア
Tattoos not allowed (day visit)
Thermae-yu Shinjuku
テルマー湯 新宿店
OK if covered (day visit)
Maenohara Onsen Sayanoyudokoro
前野原温泉 さやの湯処
OK if covered (day visit)Private bath
Tokyo Somei Onsen SAKURA
東京染井温泉SAKURA
Tattoos not allowed (day visit)
Jindaiji Onsen Yumori no Sato
深大寺天然温泉 湯守の里
OK if covered (day visit)
Ofuro no Ousama Oimachi
おふろの王様 大井町店
Tattoos not allowed (day visit)
Day trips from Tokyo
The same list for places you can reach from Tokyo and be back the same day.