In the first financial disclosure by either side in the referendum campaign, Better Together said it had received £1.1m since its launch last June, almost £900,000 from 10 large donors, and the rest from about 10,000 smaller donors.
The preponderance of business people is a blow to Alex Salmond, who has made a stronger economy a cornerstone of the SNP's case for independence.
Among the big donors was Douglas Flint CBE, the Glasgow-born chairman of global super-bank HSBC, which on Friday the First Minister described as "the most Scottish bank in the world".
The largest cheque, for £500,000, came from Ian Taylor, a Scots oil trader with a major stake in the Harris Tweed industry, after a meeting on Lewis with Alistair Darling, the Better Together leader and former Labour Chancellor.
Taylor, chief executive of Vitol Plc, has given the Conservatives £550,000 since 2006.
Although most of the large donors are registered to vote in Scotland, Taylor is not, prompting calls from the Yes camp for donations in excess of £500 to be restricted to those actually voting in the referendum.
Ten individuals gave Better Together more than £7500, bringing the total raised through large donations to £891,000. Another £54,066 was raised from 27 middle-tier donors who gave between £500 and £7500. The remaining £173,385 came from 9494 people giving less than £500, most of it online. The total banked to date is £1,118,451.
Six business people have also pledged a further £1m in donations to the campaign, although this has yet to be translated into hard cash.
The peak in donations coincided with a row last autumn about whether Salmond had lied about the SNP government's legal advice on the status of an independent Scotland in the EU.
Apart from a few small sums from branches of the train drivers' union Aslef, Better Together said all of its donations were from individuals rather than groups or political parties.
The disclosure is entirely voluntary as there is no legal requirement for the campaigns to declare donations made outside the final 16-week "regulated period" before the ballot on September 18, 2014.
It puts immediate pressure on the rival Yes Scotland campaign to declare its donations, something it has repeatedly delayed doing in spite of promising regular voluntary disclosures.
Multi-million-selling Scots crime writer CJ Sansom, who recently described the SNP as "dangerous", gave £161,000; former Inverness Caledonian Thistle chairman Alan Savage gave £100,000; Peterhead businessman Charles Richie gave £50,000; and HSBC chairman Douglas Flint gave £25,000.
Speaking at the Carnegie Council for Ethics in International Affairs in New York on Friday, Salmond said HSBC "in many ways is the most Scottish bank in the world now. Founded by Scots, run by Scots, on the principles of Scottish banking. Hence one reason why it's survived the winds better than other institutions".
Other large donors included the late Gordon Baxter, president of the Baxter Food Group.
Better Together has already spent about £500,000 on set-up costs, salaries and campaigning, and expects to spend well in excess of £1m before the start of the regulated period on direct mail to voters plus TV, radio, press and cinema advertising.
Under the proposed referendum rules, Better Together and Yes Scotland will each be allowed to spend up to £1.5m during the regulated period, while the SNP will be allowed to spend £1.344m, Labour £834,000, the Tories £396,000, the Scottish Liberal Democrats £201,000, and the Greens £150,000.
Better Together campaign director Blair McDougall said he felt "humbled" that almost 10,000 people had chosen to contribute in a time of austerity, but warned there could be no room for complacency, especially if the SNP tried to use public money to advance the Yes campaign.
And he urged Nationalists not to lash out at those giving money in support on the Union.
"Thus far in the campaign we have seen personal attacks on those who have spoken out against the nationalists. I can only hope that we do not see the usual patterns of behaviour emerge and that the nationalists respect the fact that there are two sides in the debate."
Yes Scotland said it would publish its donations soon, but offered no date for doing so.
A spokesman said: "We believe the appropriate position is that both campaigns should agree that any donations above £500 – the legally recognised level over which money given becomes a "donation" – should come only from those registered to vote in Scotland's referendum. Yes Scotland is sticking firmly to that."