The hotel collaboration between the Welsh Rugby Union, property developer Rightacres and Celtic Manor owner the Celtic Collection, will open in October and has been renamed the Parkgate.
The property, formerly the old post office and county court buildings on Westgate Street in Cardiff, was initially called the Westgate hotel but will instead take its name from the Parkgate building that housed the old post office.
The period features of the Grade II-listed building, which dates from the turn of the 20th century, have been restored, and when it opens the hotel will have 170 guest bedrooms and suites, a signature restaurant and bar, a tea lounge and a rooftop spa.
The Celtic Collection chief executive Ian Edwards said: "At a time when we are beginning to reopen and bounce back in tourism and hospitality, we are delighted that the Parkgate hotel will open this October in time for the autumn internationals.
"The Parkgate is going to be a fantastic, year-round addition to Cardiff's hotel landscape and it will be an extra special place to be on the big match days that create such an amazing atmosphere in the city."
WRU chief executive Steve Phillips said: "The Parkgate hotel will put guests right at the heart of the match day action and is the perfect location for exploring the city centre. It is another fantastic addition to what we are able to offer our visitors for rugby matches and other sporting fixtures, music concerts and corporate events."
Rightacres chief executive Paul McCarthy added: "The city centre of Cardiff has been lacking a luxury hotel for a long time and it is especially pleasing to incorporate two iconic but unused buildings in the hotel. As well as the connection to Principality Stadium, the significant commercial regeneration going on in this part of the city will only add to the appeal of the Parkgate hotel."
Images: Goddard Littlefair interior design