The retailer says the concept is in response to customer demand and forms part of its long-term growth strategy.
It will provide treatments such as facials, manicures, pedicures, eyebrow/eyelash tinting and threading from premium brands including Clarins, Elemis, Liz Earle, Decleor, Blink and Jessica.
The first spas will open in its Reading and Cheadle department stores this summer as part of planned store refurbishments.
John Lewis plans to invest £250m to develop “innovative retail concepts” alongside its e-commerce operations.
Andy Street, managing director, says: “The beauty spa concept is the start of a more holistic service offering to customers, and our investment means we can continue to improve the customer experience by adding new and exciting concepts.”
John Lewis reported a strong set of Christmas figures despite the difficult conditions on the high street. The department store chain recorded sales of £545m for the five weeks to 1 January, a 9% increase on the previous year. Like-for-like sales rose 7.6%.