The 100-room property, which is located in Marmari, is the second of the operator’s new “lifestyle hotels”.
Its Casa Cook Rhodes property opened last summer as an adults-only resort but its new Kos hotel will also cater for families.
The property features a collection of one and two-storey villas with five different room types from “Double Standard” to “Villa Suites”.
Cook said the property’s designed had been influenced by the cubist architecture found on Kos.
All rooms at Casa Cook Kos feature a private veranda or terrace and come with rain showers, mini-bars and free Wi-Fi.
Guests can enjoy its Beach Club facilities which is home to a bar, lounge, restaurant and pool.
Activities on offer include paddle boarding, horse riding on the beach and yoga classes on the terrace.
The hotel also has a gym, indoor pool and spa.