The major competition – which includes events in the Black Country – has seen 6,500 athletes and officials turn out from 72 Commonwealth nations and territories.
It has been backed through £778 million of public funding including £594m from the Government and has been the quickest-delivered games in its history.
The event has taken four and a half years to organise, rather than the usual seven, and boasts the biggest para-sport programme in history, organisers have confirmed.
Prime Minister Boris Johnson said: “The UK rightly has an outstanding reputation for hosting major sporting events, and the Commonwealth Games in Birmingham will be another fantastic opportunity to showcase the best of Britain on a global stage.
“Not only will we be celebrating sporting success, we will also be strengthening the crucial ties between our 72 nations and territories – bringing businesses and governments from across the world together to encourage trade and boost economic growth that will leave a lasting legacy for years to come.
“Good luck to all the athletes competing – let the Games begin!”
The Prince of Wales – accompanied by The Duchess of Cornwall – will represent The Queen and officially open the competition at the Alexander Stadium in Birmingham in front of more than 30,000 spectators and an estimated television audience of over one billion people.
Athletes will compete in 11 days of sport across the West Midlands and more than one million tickets have been sold for events across the region.
Culture Secretary Nadine Dorries said: “Today the eyes of the world turn to Birmingham. We have an incredible 11 days of sport and I know that fans from across the home nations will get right behind our athletes.
“Beyond the medals won and records broken, these Games will deliver a fantastic legacy – sporting, cultural and economic – for the people of Birmingham and the West Midlands.”
President of the Commonwealth Games Federation, Dame Louise Martin said: “These Games have been four and a half years in the making and Birmingham has done an incredible job, overcoming challenging circumstances, to prepare for the biggest ever Commonwealth Games.
“I’m absolutely delighted that over 1 million people will be attending and more than a billion people watching around the world to share in the excitement. I have no doubt that Birmingham 2022 will be a spectacular Games for the host city, and the Commonwealth.”