The Complete Guide to Japan’s “Onsen” and “Sento” Culture

2026.08.5

The Complete Guide to Japan’s “Onsen” and “Sento” Culture

“Japanese hot springs (Onsen) and public baths (Sento) are not merely places to wash your body—they represent an experiential relaxation culture that purifies the mind and body, connects you with the community, and unifies you with nature.”

— This is the most crucial perspective for truly appreciating Japanese bathing culture.

Here, we provide a clear and comprehensive guide to Japan’s bathing culture, covering everything from the differences between Onsen and Sento, their history, bathing etiquette, rules regarding tattoos, and the famous hot springs that represent Japan.

For foreign travelers: The experience of “getting completely naked in front of strangers and soaking in the same water” might be surprising at first. However, once you understand the background and rules, it will transform into “one of the most relaxing and unforgettable experiences of your stay in Japan.”

1. Similar Yet Distinct: The Crucial Differences Between “Onsen” and “Sento”

While Onsen and Sento may look similar at first glance, their origins and roles are completely different.

Feature	Onsen (Hot Spring)	Sento (Public Bathhouse)
Water Quality	Naturally occurring thermal or mineral water from underground. Contains minerals (sulfur, salt, carbonic acid, etc.) governed by legal standards.	Heated water using tap or well water boiled with heaters/boilers (some feature medicinal or artificial carbonated baths).
Primary Purpose	Toji (recovery from illness or fatigue), travel, and relaxation.	Daily bathing, hygiene maintenance, and local community interaction.
Location	Mostly in resort areas or mountain regions surrounded by nature. Often attached to ryokan (traditional inns) or resorts.	Located in residential and urban areas, deeply integrated into daily local life.
Pricing & System	Varies widely depending on the facility, day use, or overnight stays (ranging from ~$10 to hundreds of dollars).	Fixed public rates set by each prefecture (around 550 yen in Tokyo).

2. The History and Evolution of Onsen and Sento

The History of Onsen: Nature Worship and “Toji”

Ancient to Medieval Times: In volcanic Japan, humans are said to have started using hot springs after observing injured animals healing themselves. With Buddhism’s spread, “cleansing the body” became a virtuous deed, leading to temple baths.
Edo Period (17th–19th Century): The culture of Toji (温泉療養 / hot spring therapy) became established. Farmers and commoners stayed for weeks or months to recover from fatigue. Onsen rankings (styled after Sumo rankings) were wildly popular.
Modern Times: Long-term Toji shifted toward 1- or 2-night resort trips. Recently, fueled by a sauna boom and tourism, diverse spa facilities and luxury resorts have emerged.

The History of Sento: From Everyday Lifeline to Culture

Edo Period: To prevent fires, private baths in individual homes were prohibited in Edo (Tokyo). People used neighborhood Sento (mixed-gender back then), which served as “local community hubs” to exchange news.
Showa Period (Mid-20th Century): After WWII, hand-painted murals of Mt. Fuji appeared on Sento walls, becoming an iconic cultural staple where all ages gathered.
Modern Times: Despite home bath proliferation reducing numbers, Sento are reborn as cultural trends via designer facilities and modern sauna-specialized baths.

3. Essential Rules and Etiquette for Enjoying Baths in Japan

Japanese bathing culture is packed with thoughtful practices designed to ensure everyone shares the water comfortably and hygienically. Following these steps ensures a pleasant experience for both you and those around you.

1. Remove all clothing in the changing area: Swimming suits and underwear are strictly prohibited. Remove all jewelry, take off all clothing, and place them in a basket or locker. You should only bring a “single small hand towel” into the bathing area.

2. Do Kakeyu (Rinsing body): A crucial etiquette rule to keep the bathwater clean. Before entering the tub, always wash your body at a shower station or pour warm water over yourself starting from your feet (kakeyu) to rinse off dirt.

3. Soak in the tub (Do not put towels in the water): Enter the tub slowly. Never submerge your hand towel into the bathwater. Place it on your head or set it on the edge of the tub. If you have long hair, tie it up with a hairband.

4. Wash your body: Be mindful not to splash soap suds on others. Wash yourself using soap and shampoo at the shower station. Return used basins and stools to their original spots and rinse away any remaining foam.

5. Wipe yourself before returning to the changing area: A courtesy to keep the floor dry. Before stepping out of the bathing area, wring out your small hand towel thoroughly and lightly wipe off excess water from your body so you don’t wet the floor in the changing room.

💡 Prohibited Actions to Keep in Mind

Swimming or diving in the tub.
Scrubbing or washing your body inside the tub.
Bringing smartphones or cameras into the changing room or bathing area (strictly forbidden to prevent voyeurism).
Bathing while intoxicated (forbidden for safety reasons).

4. Tattoos and Japanese Onsen / Sento

One of the most frequent questions from international travelers is, “Can I enter an Onsen if I have a tattoo?”

Why do many Japanese facilities prohibit tattoos?

Historically in Japan, tattoos (Irezumi) have been associated with anti-social organizations (Yakuza). As a rule to prevent other guests from feeling intimidated or uncomfortable, many private Onsen facilities and “Super Sento” (large modern bathhouses) still maintain a policy of denying entry to anyone with tattoos.

Options for Travelers with Tattoos

In recent years, the situation has been changing gradually due to the influx of foreign travelers with cultural or fashion tattoos.

1. Local Public Sento

Many neighborhood public bathhouses (especially in Tokyo) operate as public infrastructure, meaning many locations do not deny entry based on tattoos.

2. Cover with Seals

Facilities like Hoshino Resorts permit entry if small, palm-sized tattoos are completely covered with medical tape or specialized cover-up seals.

3. Private Baths

Booking a private bath (Kashikiri-buro) or a Ryokan room with an open-air bath lets you enjoy bathing 100% freely regardless of tattoos.

4. Tattoo-Friendly Towns

Areas like Kinosaki Onsen in Hyogo Prefecture welcome tourists town-wide, allowing tattoos in all seven of its public bathhouses (Sotoyu).

5. Japan’s Famous “Three Great Hot Springs” You Must Visit

These three hot spring destinations—known as the “Three Famous Hot Springs of Japan” (Nihon Sanmeisen)—were praised by the Muromachi-period poet-monk Banri Shukyu and the Edo-period Confucian scholar Hayashi Razan. They represent the pinnacle of history, water quality, and culture in Japan.

① Arima Onsen (Kobe City, Hyogo Prefecture)

History & Features: Mentioned in ancient texts like the Nihon Shoki (Chronicles of Japan), Arima is one of Japan’s oldest hot springs, loved by figures like Toyotomi Hideyoshi.

Water Appeal: Famous for two water types: Kinsen (Gold Spring), rich in iron/salt turning reddish-brown, and Ginsen (Silver Spring), a clear carbonated/radium spring leaving skin feeling smooth.

Highlights: Retro slopes, historic streets, and street food like famous carbonated rice crackers (Tansan Senbei).

② Kusatsu Onsen (Kusatsu Town, Gunma Prefecture)

History & Features: Boasts the highest natural gush rate in Japan (over 32,300 liters per minute).

Water Appeal: Strongly acidic (pH around 2) with powerful antibacterial properties. Famous saying: “It can cure every ailment except lovesickness.”

Highlights: The iconic steaming Yubatake (Hot Spring Field) center, and traditional “Yumomi” water-cooling performances.

③ Gero Onsen (Gero City, Gifu Prefecture)

History & Features: Set along the clear Hida River, cherished as a major stop along the historic Kiso Road.

Water Appeal: Alkaline simple hot spring featuring an amazingly smooth, “silky/viscous” texture. Renowned nationally as a “Bath of Beauty” (Bijin-no-yu).

Highlights: Footbaths (Ashiyu) scattered throughout town, surrounded by nature and gourmet Hida beef.

6. Post-Bath Bliss: The “After-Bath Drink” Culture

The time spent right after stepping out of an Onsen or Sento is another essential element of the Japanese bathing experience.

Milk / Coffee Milk: Drinking ice-cold bottled milk or coffee-flavored milk right after warming up your body is a classic Japanese tradition.
Onsen Tamago / Ramune: Soft-boiled eggs cooked in natural hot spring heat (Onsen Tamago) and nostalgic marble-soda (Ramune) are iconic treats.
Sauna Food (Sa-meshi): Enjoying a hearty, flavorful meal (curry, ramen, or vitamin-replenishing drinks) after sweating is a popular modern trend.