The 365-room full-service hotel is close to the entrance of the Capitol and University of Texas’ Football Stadium and Frank Erwin Center.
Spanning 15 storeys, the hotel houses 17,250ft² of meeting and function space, including a 9,650ft² ballroom, plus an indoor/outdoor pool and a business centre.
It also features a Sheraton Core fitness centre, the Landmark Restaurant and a lobby bar.
Sheraton Austin Hotel will continue to be managed by an affiliate of HEI Hotels & Resorts, which operates six Sheratons and a total of 18 Starwood properties in the US.
CWI holds an 80% interest in the joint venture and JMI Realty, a private real estate investment and development company based in Austin, holds the remaining stake.
Following the acquisition, the hotel will undergo a comprehensive renovation including guestrooms and public spaces at an estimated cost of over $6m.
CWI chief executive Michael Medzigian said: "In combination with our recently announced acquisition of the select-service Hyatt Place Austin, we believe the strength of the Sheraton brand in the full-service sector, along with the property’s location and physical attributes, give us broad sector exposure in the strong Austin lodging market.
"In addition, this investment is consistent with our strategy of creating joint ventures with experienced owners to maximise the current value of uniquely positioned assets, create a solid financial platform for future operations and achieve attractive risk-adjusted returns for our investors."