The pro-Union Better Together campaign group has received £1.6 million in donations since April this year, it has been revealed.
Figures published by the group showed that the biggest donor, Argyll businessman Donald Houston, gave £100,000 and a further £500,000 through two of his companies.
Investment banker Andrew Fraser donated £200,000 and Alan Savage, chairman of Inverness-based recruitment group Orion, contributed £150,000.
Author Christopher Sansom gave £133,000.
Since April more than 17,000 people have contributed to the campaign directed by Blair McDougall, mostly giving sums of less than £500.
The group has received almost £2.8 million since it was established in May 2012.
Among the other donors listed this year are former banker and Arsenal chairman Sir Chippendale Keswick, who gave £23,000.
Better Together director Mr McDougall said the group was “humbled” by the number of supporters who had contributed financially.
The SNP said the identity of the Better Together donors highlighted the “Tory roots” of the pro-Union campaign.
The Yes Campaign said it will publish further information about donations it has received in due course.