Sento: Japan's Neighborhood Bathhouses, and Why They're Disappearing

Onsen get all the attention, but the bathhouse most Japanese people actually grew up with is the sento — and there are now barely a tenth as many as there used to be.

Sento vs onsen: the actual difference

The words get used interchangeably by visitors, but they mean different things. An onsen draws on natural hot spring water and is regulated as such. A sento (銭湯) is a public bathhouse using ordinary heated tap water, classified under Japanese law as a "general public bathhouse" — and because of that classification, its entry fee is capped by the prefecture, not set by the owner. Onsen etiquette — wash before entering the communal tub, no soap in the water, no swimsuits — applies at sento too, but the atmosphere is different: less resort, more neighborhood institution.

As of 1 August 2026, Tokyo's regulated adult sento fee rose from ¥550 to ¥600 — the first increase since a ¥30 rise in August 2024. Children aged 6–11 still pay ¥200, and under-6s pay ¥100. Even after the rise, it remains one of the cheapest indoor activities in central Tokyo.

Where the Mount Fuji murals come from

The single most recognisable sento image — a giant painted Mount Fuji filling the wall above the baths — has a specific, dateable origin. In 1912, the owner of Kikai-yu, a bathhouse in Tokyo's Chiyoda ward, wanted to make bathtime more appealing to children during a renovation and commissioned a Shizuoka-born painter, Hirosuke Kawagoe, to decorate the wall. Kawagoe painted the mountain from his own home prefecture. It was popular enough that other sento began commissioning their own versions, and the painted mural — Fuji or otherwise — became a genre of its own.

A neighborhood sento — recognisable by the noren curtain and, often, a tall chimney out back.

Why they're disappearing

Sento existed because most homes didn't have their own bath. That stopped being true decades ago — private baths became standard in Japanese housing through the postwar decades, and the customer base sento were built for largely evaporated. The number of registered public bathhouses in Japan peaked at 17,999 in 1968. By 2025, that figure had fallen to 1,562 — a 91% decline.

The remaining sento are now being squeezed from another direction: fuel costs. Sento rely on large boilers, historically fired with heavy oil, to heat enormous volumes of water daily. According to Teikoku Databank, a 30% rise in fuel costs cuts the average Japanese business's operating profit by about 5% — but for sento operators specifically, the same fuel spike wipes out roughly 30% of profit, because heating water is most of the cost structure. Seven sento businesses formally shut down in fiscal 2025 alone, and owner age is compounding the problem: many of the remaining sento are run by operators in their 70s and 80s with no succession plan.

The chimney is a giveaway — most sento built before the 1970s have one, even though modern boilers rarely need it.

The unlikely thing keeping some of them alive

Not every trend is working against sento. Japan's sauna boom — a genuine cultural moment, built around the idea of totonou (reaching a specific state of relaxed clarity through hot-cold-rest cycles) — has pulled a younger crowd back into old bathhouses, several of which have added or upgraded saunas rather than closing. A handful of sento in Tokyo and Osaka have become minor destinations in their own right off the back of this, packed with twenty- and thirty-somethings on weekday evenings in a way that would have been unthinkable ten years ago.

Visiting one

Bring your own small towel and toiletries, or rent or buy them on site for a small fee — don't expect English signage. Wash and rinse thoroughly at the stall before getting into the communal tub; the water is shared and reused all day. Tattoo policies vary shop to shop and tend to be stricter than at many hotel onsen, so it's worth checking ahead or covering up if you have one. And go in the early evening if you want to see a sento the way most regulars do — locals dropping in on the way home, not tourists on a schedule.