An Accidental Discovery
Our journey began when Eric Shinichi, founder of IREN Shizen, visited a hot spring resort in the mountains of Hokkaido Japan. He made a chance discovery of the secret behind the locals’ naturally glowing skin: their weekly soaks in the rejuvenating onsen water known as “Bijin-no-yu”, which means hot spring of beauty.
Fascinated by the skin-regenerating effects, he was inspired to share this beauty secret with the world by infusing this legendary healing water into his skincare formulations, culminating in the creation of BIYUSEN™.
From Onsen to Our Labs
Through the marvel of biotechnology, we have recreated this precious onsen water in our labs, ensuring its purity and potency are preserved in every drop.
Introducing BIYUSEN™, this revolutionary lab-grown ingredient is now the cornerstone of every IREN Shizen product, infusing each with the transformative powers of Japan's most exclusive onsen.
The Birth of Onsen Facial
Eric’s vision extended beyond skincare—he sought to recreate the full onsen experience in a transformative facial ritual. At Ikeda Spa, he and his team designed a treatment that mirrors the essence of Japan’s thermal springs, from steam-infused towels that mimic soothing waters to a detoxifying, mineral-rich mask that purifies and replenishes the skin.
More than just a facial, this ritual embodies the serenity and renewal of the onsen, allowing you to experience a touch of Hokkaido’s beauty secrets—where nature’s healing powers meet the precision of science.
PURCHASE ANY 3 SERUMS TO REDEEM
FREE $120 Facial Voucher & 15ml Flowers in Bloom
Need help with choosing your serums?
No two skins are alike, and neither are their concerns—dry, sensitive, and lined with time’s whispers, often all at once. Your skin deserves a formula as unique as you are, a fusion of potent actives crafted to meet your every need. Unsure which serums to combine? Our dermatologist is here to guide you.
Discover the Power of Onsen Water
The story of IREN Shizen began with nature’s best-kept secret—rare "moor" onsen water. Through years of research, we transformed it into BIYUSEN™—a powerful, skin-renewing complex infused in every product. Feel the luxury as your skin is restored to its ultimate, radiant splendor.
Fulvic acid
Boosts skin's defense with powerful antioxidant, aiding oxygen and water absorption
Humic acid
Extends hyaluronic acid's life, boosts skin moisture, and slows wrinkle formation.
Hymatomelanic acid
Smooths skin texture, heals micro-wounds, and accelerates cell renewal.
Visible Results in 28 Days
Our supercharged serums, powered by BIYUSEN™, undergo rigorous testing, ensuring potent efficacy for timeless, radiant skin.
| 100% | agree skin feels softer, smoother and more supple |
| 97% | agree skin feels instantly hydrated with a healthy, radiant glow |
| 94% | agree skin looks firmer, lifted and feels more elastic |
A Facial that Recreates the
Onsen Experience
This is more than just skincare—it’s an immersive ritual that mirrors the deep relaxation and renewal of a real onsen soak.
Steam Infusion
Just like stepping into a thermal hot spring, this opening step softens and preps the skin, allowing nutrients to be absorbed deeply.
Biyusen™ Hydration
A luxurious blend of onsen-derived minerals is infused into the skin, delivering intense hydration, detoxification, and nourishment.
Cooling Therapy
Inspired by the contrast bath technique of Japanese onsens, this final step tightens pores, firms the skin, and seals in moisture for a lifted, youthful glow.
Steam Infusion
Just like stepping into a thermal hot spring, this opening step softens and preps the skin, allowing nutrients to be absorbed deeply.
Biyusen™ Hydration
A luxurious blend of onsen-derived minerals is infused into the skin, delivering intense hydration, detoxification, and nourishment.
Cooling Therapy
Inspired by the contrast bath technique of Japanese onsens, this final step tightens pores, firms the skin, and seals in moisture for a lifted, youthful glow.
IKEDA SPA
We partnered with Ikeda Spa to bring the authentic healing power of Hokkaido’s hot springs to life. As Singapore’s premier Japanese spa, they share our passion for traditional beauty rituals and modern skincare innovations. With their expertise in immersive wellness, our Onsen Facial offers a deeply rejuvenating and authentically Japanese experience.
Won 43 awards and still counting...
"The massage was super shiok and relaxing. My therapist know exactly what to do to make you feel good. I walk out feeling lighter and super chill. It's the best kind of 'me time' anyone could ask for!"
"I think it starts from the very first moment you step into Ikeda, it's very welcoming, people feel very genuine, sincere and not pushy like some of the spas I might have visited before. The whole set-up was private and cozy as well, very clean I would do it again in a heartbeat."
"I love how authentic the experience here is. I like the fact that I can do lots of different types of massages here on top of my onsen and there’s a variety of treatments here. In addition to that, I get this very good service here so I think everything here is exceptional. So I would definitely come here if I want to pamper myself."
"The warm melted candle massage on my skin was so soothing and it was actually very relaxing along with the long kneading massage technique! All I can say is that it was a well-rested and pure blissful 90-minute massage!"
"Thank you Ikeda Spa. Now I understand why my friend is recommending me to check you out... The place feels calm and the people there are super nice. They give really good massages that make you feel relaxed and happy. It's clean and has a peaceful vibe that makes all my stress go away."
"I highly recommend Ikeda Spa for its excellent service, as well as its courteous, knowledgeable and friendly staff. The whole place is super clean, and it has a calm feeling that makes me happy. It's like a mini-vacation from all the busy stuff in my life!"
"I really love the onsen bath. The water is just the right temperature and it feels so good to just soak and relax. It's always clean and quiet, which makes it easy for me to sit back and forget about everything else for a while. Thank you Ikeda Spa."
"Going to Ikeda Spa was the best treat ever. I had the most relaxing time in the onsen bath—it felt like all my worries just floated away. And the massage after that? Amazing! Big thanks to my BFF for making me try it. Everyone should have a friend who gets you a day at Ikeda Spa!"
"I've tried lots of scrubs, but the Rice Bran Whitening Scrub at Ikeda Spa is my favorite. It's gentle on my skin and makes it feel super smooth. After the scrub, my skin looks bright and feels so soft—like I can't stop touching it!"
Take a Quick Spa Tour
Terms & Condition
How do I book my Free Onsen Facial?
You can book your appointment with a unique link given after purchase. Please quote the discount code received in your email upon booking (with a minimum purchase of $180).
Who is eligible for this promotion?
This promotion is valid for customers who spend a minimum of $180 on IREN Shizen products.
What do I need to bring to redeem this promotion?
Please present your e-voucher and purchase receipt during your appointment for verification. We reserve the right to cancel your booking if either the e-voucher or purchase receipt is not provided.
Can I transfer my voucher to someone else?
No, the voucher is non-transferable and can only be used by the person who made the purchase.
How long is my voucher valid for?
The voucher is valid for 6 months from the date of receipt.
Do I need to provide my credit card details to secure a booking?
Yes, credit card details must be provided to secure your appointment.
Do I need to make a reservation in advance?
Yes, reservations are required and subject to availability. We recommend booking at least one month in advance.
What is the cancellation policy?
A 48-hour cancellation notice is required. If you fail to cancel within this time frame, your free facial will be revoked.
Is this promotion available to everyone?
This promotion is valid only for local residents of Singapore. Proof of residency is required.
Can I bring someone with me to my appointment?
No, this offer is strictly for a single pax per appointment.
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