Tony Abbott has declared Australia is "once more open for business" in claiming victory in Saturday's election.
He acknowledged the service to the country of outgoing Prime Minister Kevin Rudd, following the Labor leader's concession speech.
"I now look forward to forming a government that is competent, that is trustworthy," he told a packed crowd at the Four Seasons Hotel in Sydney.
Liberal supporters cheered Mr Abbott as he spelled out the coalition's election win over Labor.
"I can inform you that the government of Australia has changed," he said.
"For just the seventh time in 60 years the government of Australia has changed."
The coalition had won 13 seats clearly with 10 seats still in play, Mr Abbott said.
"And I can inform you that the Australian Labor Party vote is at the lowest level in more than 100 years," he said.
He confirmed Mr Rudd had called him to concede defeat.
"He has been the prime minister of this country not once but twice so I acknowledge his service to the nation of Australia," he said.
Mr Abbott said the people of Australia had shown they would determine who would govern or be prime minister of the country.
"Today the people of Australia have declared that the right to govern this country does not belong to Mr Rudd or to me or to his party or to ours but it belongs to you, the people of Australia," he said.
"And you will punish anyone who takes you for granted."
Mr Abbott said his government would be purposeful, steadfast and methodical in setting about delivering on its commitments to the Australian people.
"From today, I declare that Australia is under new management and that Australia is once again open for new business," he said.
Mr Abbott said the governor-general would swear in his government in the "next week or so".
He promised again that the new government understood its potential and limits and guaranteed "no surprises and no excuses".
"A government that accepts that it will judged more by its deeds than by its mere words," he said.
He promised that in "three years time" the carbon tax would be gone, the asylum seeker boats would be stopped, the budget would be on track for surplus, and the roads of the 21st century be under construction.
Mr Abbott said hundreds of thousands of people had voted Liberal and National for the first time in their lives.
"I give you all this assurance - we will not let you down," he said.
"A good government is one that governs for all Australians, including those who haven't voted for it.
"A good government is one with a duty to help everyone to help maximise his or her potential - Indigenous people, people with disability and our forgotten families as well as those who Menzies described as lifters not leaners.
"We will not leave anyone behind."
Mr Abbott said he was humbled at the prospect of becoming prime minister.
"I'm both proud and humble as I shoulder the duties of government," he said.
He thanked his staff, coalition members, and the voters of his Sydney electorate of Warringah who returned him as their federal member for his eighth consecutive term.
"I thank my family who have given me so much support ... through a public life," Mr Abbott said.
"Most of all I thank you the people of Australia who have just given me the greatest honour and the highest responsibility that any member of parliament can have.
"I'm both proud and humble as I shoulder the duties of government."
He thanked his many friends in the audience, and paid tribute to their "long long journey".
"May it continue, and may it help to bring better times to this great country of which we are all so very, very proud."
He was then joined on stage by his wife Margie and three daughters Louise, Bridget and Frances.
At this point, they were joined on stage by a young man who had everybody asking "who's that guy".
The man stood beside the family smiling for photographs for about 20 seconds, before security jumped on stage and dragged him off to the side.