Onyx Day Spa

2743 Castro Valley Blvd, Castro Valley, CA 94546

COVID-19 Updates

We have installed safety glass shields to protect both our clients and our workers.

Business Information
Current Business Hours


10:00 am – 8:00 pm


10:00 am – 8:00 pm


10:00 am – 8:00 pm


10:00 am – 8:00 pm


10:00 am – 9:00 pm


9:00 am – 7:00 pm


10:00 am – 4:00 pm


Onyx is an upscale day spa offering customized services in the heart of Castro Valley.


Onyx Day Spa formerly known as the Spa has been in business for over 15 years. Customer service is our top priority! We have a staff of highly trained professionals who offer consistent quality service to our customers.


The professionals at Onyx Day Spa offer exclusive services including Hot Stone massage, body wraps, body scrubs, facials, microdermabrasion, facial peels, manicures, pedicures and waxing. We are excited to offer custom Organic Air brush spray tans and Eye Lash Extensions as well. We exclusively use Image skin care products in all of our Facial treatments. We accommodate group spa days, have on going package deals and offer monthly specials.

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