Certified Onsen Sommelier
Onsen, Done Right
I fell in love with onsen years ago and got certified as an Onsen Sommelier so I'd stop half-guessing the details myself — which places actually allow tattoos, which ones are worth a two-hour train ride, and which are better as a spontaneous stop than a planned trip. That's what the guides below break down, and what I'll answer directly if you ask.
Onsen, ryokan, sento — not the same thing
"Onsen" gets used as a catch-all, but the way you'll actually experience one splits into a few distinct forms.
- Ryokan stay
- A room for the night built around the bath — dinner, breakfast, and usually two soaks: one before dinner, one before you check out.
- Day visit
- No reservation, no room. Pay at the front desk and you're bathing within ten minutes.
- Kashikiri (private bath)
- The whole bath locked to just your group for a set block of time — search "kashikiri" if you want to book one yourself.
- Sento
- Heated tap water, not a spring, and priced by the prefecture rather than the owner — ¥570 flat in Kanagawa. Locals treat it as a habit, not a trip.
New to onsen? Have a question?
Not sure what to bring, whether tattoos are allowed, or how the etiquette works? Ask me anything about onsen basics and I'll write back within a couple of days. It's free. (Want onsen and ryokan picked specifically for your trip? That's what the custom itinerary below is for.)
Onsen & Hakone Guides
Heiwajima Onsen: A Real Natural Hot Spring Near Haneda Airport
A natural hot spring pulled from 2,000 metres underground, a few minutes from Haneda Airport — plus a late-night stay plan built for anyone flying in or out on an early or late flight.
Onsen vs Sento: What's Actually the Difference?
An Onsen Sommelier breaks down what actually separates an onsen from a sento — the legal definition, how locals really use each one, and why the tattoo question isn't as simple as people think.
A Hakone Day Trip: Soba at Akatsukian and Onsen at Tenzan
A day trip to Hakone with a friend, built around just two stops — bamboo charcoal soba at Akatsukian and a deep dive into Tenzan Onsen's two hot spring sources, from an Onsen Sommelier's perspective.
Can a Hot Spring Really Make Your Skin Softer? My Search for Japan's Beauty Water
I'd heard the phrase bijin no yu — beauty water — my whole life without knowing what it actually meant. So I went looking for it, starting with Tokyo's black-water onsen and my home onsen in Yokohama.
Irodori Yukashiki Hana to Hana: A Ryokan Review from an Onsen Sommelier
A ryokan review of Hana to Hana in Yunishigawa Onsen, Tochigi — covering the alkaline hot springs, irori hearth dinner, sake tasting, and what makes this mountain retreat worth the trip.
Nagominoyado Hanagokoro Review: A Private Onsen Ryokan in Hakone's Gora
A small adults-only ryokan in Gora with 8 rooms, each with its own private outdoor bath. Here's what the onsen water is actually like — and why August in Hakone makes more sense than you'd expect.
How to Use an Onsen in Japan: A First-Timer's Guide
A certified Onsen Sommelier's guide to using a Japanese hot spring properly — including the five bathing principles.
Want a whole day built around it?
Get a personalized Kanagawa day trip itinerary that includes the onsen that fits your trip — ¥5,000, delivered as a PDF.
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