British Prime Minister David Cameron and Salmond signed the agreement Monday at the Scottish government headquarters in Edinburgh, scotsman.com reported.
"The Edinburgh agreement, signed by the Scottish and U.K. governments today, marks a significant step in Scotland's home rule journey," said Salmond. "Importantly, it will ensure that the biggest decision the people of our country will make for many generations is made here in Scotland for the benefit of all of those that live and work here."
The referendum will include only one question, whether Scotland should become an independent country, The Daily Telegraph reported.
"The Scottish government has an ambitious vision for Scotland: a prosperous and successful European country, reflecting Scottish values of fairness and opportunity, promoting equality and social cohesion," Salmond added.
The British government rejected a second question, wanted by Salmond, which would have allowed Scotland to gradually assume the power to tax and control some areas of public spending.
A similar referendum on Scottish independence is not scheduled for Britain.
Michael Moore, Britain's Scottish secretary, said he was confident the referendum, to be held in the fall of 2014, would be rejected by Scots and that Scotland would stay in the British union.
A poll published last week said Scottish support for independence has fallen. A survey of 995 adults found 53 percent wanted to stay with the Union, while 28 percent wanted independence.