A Saturday voting day will join "devo max" and the lowering of the voting age to 16 in the options set out in the SNP Government's consultation on the rules for the independence referendum, it emerged last night.
But the document, to be unveiled in Parliament on Wednesday before an international press launch, will not seek views on whether a referendum held under Holyrood's existing powers would be legal.
The idea of a Saturday plebiscite was suggested at a recent Holyrood conference as a way of increasing turn-out. Scottish ministers are open-minded on the idea.
Every UK General Election since 1935 has been held on a Thursday, as have all Holyrood elections and the referendum on Scottish devolution in 1997.
A Saturday referendum in the autumn of 2014 could see the vote held on August 8, the 77th birthday of First Minister Alex Salmond's wife, Moira.
The document will also see Salmond confirm his preference for a single yes-no question on independence in a 2014 referendum, but will also encourage the public to say whether other options, such as devolution max, should appear on the ballot paper, much to the irritation of the Westminster government.
The first minister will also ask if the voting age should be lowered to 16 for the referendum.
UK Prime Minister David Cameron yesterday insisted he would make a "positive" case for maintaining the Union, saying he would not "run a campaign that says Scotland cannot survive on its own".
However, Salmond said the Prime Minister had been "talking down Scotland for weeks", and warned him not to dictate the terms of the referendum.
"All of the baseless smears have imploded once they have been exposed to any serious analysis – from currency and defence, to EU membership, the NHS, and even that the pandas would be taken away from Edinburgh Zoo," he said.
"The anti-independence campaign will be left with nowhere to go, while the pro-independence campaign will enthuse and engage people the length and breadth of Scotland with our positive vision for the future."
The SNP consultation is expected to stick to the template set out in a Government paper on a referendum published in the last parliament.
Campaign groups will be limited to spending £750,000 each and political parties £100,000 each during the regulated referendum period, which will start around New Year 2014.
The consultation will run for three months.
A referendum bill will be introduced at Holyrood in January 2013, and should complete its passage and obtain Royal Assent by the end of the year.
The referendum would then take place a few months after the European elections due in June 2014.
The consultation will form the backdrop to talks between Salmond and the Liberal Democrat Scottish Secretary Michael Moore in Edinburgh on Friday.
Holyrood's ability to hold a competent referendum, free from legal challenge, has been at the heart of the independence debate since the Coalition launched its own consultation two weeks ago.
Salmond insists a homegrown referendum would be feasible. However, the Westminster government insists a vote on a reserved matter such as the Union would be "not law" and open to challenge.
The Coalition is offering to devolve more powers under Section 30 of the Scotland Act, but on condition the SNP drops the idea of a lower voting age and puts a single question to voters.
The SNP government had wanted a new dedicated watchdog to oversee the referendum, but now appears happy for the UK Electoral Commission to take on the role, provided it is accountable to Holyrood, not Westminster, for the occasion.
In return, Westminster is going back on having a referendum "sooner rather than later", grudgingly accepting Salmond's date of autumn 2014.
Moore welcomed the "positive signals" from Edinburgh, but also said he wanted Salmond to admit he currently lacked the power, if not the mandate, to hold a referendum.
"I hope that they will acknowledge ... a Section 30 order devolving the power is the best way to proceed. It is in the interests of the Scottish people to have a legal referendum, sooner rather than later, on one simple yes/no question."
The Coalition's continued attack on the legality of a Scotland-only referendum is likely to irk Salmond ahead of his talks with Moore.
The two men already have a history of unproductive discussions over the Scotland Bill, with an evident lack of chemistry between the hyperactive Salmond and Moore, an Eeyorish former accountant.
Salmond may save his thunder for a meeting with David Cameron next month instead.
Scottish Labour leader Johann Lamont yesterday wrote to the heads of the other Holyrood parties and Independent MSP Margo MacDonald, inviting them to cross-party talks on how to achieve "a clear, legal and decisive" referendum.
She said Salmond had refused to convene such a meeting despite being asked nine times, accusing him of being "deeply disrespectful" to others.