The figures include £270,983 in ‘short money’, which covers a payment from the House of Commons to opposition parties to help with running costs.
The SNP also received £300,000 from Morven Polson in February this year as part of a bequest.
In 2019, the last year full accounts for the SNP are available, the SNP received just under £400,000 in total in legacies left by supporters.
The legacy is the only donation above £7,500 made to the party from a member of the public reportable to the Electoral Commission, but it is the biggest single donation to the party since Colin and Christine Weir donated £250,000 each in 2017.
The additional cash comes amid a transparency row in the party over the alleged disappearance of £600,000 in crowdfunded donations.
SNP treasurer, Douglas Chapman, and high-profile MP Joanna Cherry, both resigned over a lack of transparency in the last week.
The party’s accounts for 2020 should be published in August.
The Conservative party accepted almost £6.5m in donations in the first quarter of 2021, with the largest donation of £500,000 coming from Peter Cruddas, who was given a life peerage by Boris Johnson in December 2020.
This was despite the House of Lords Appointments Commission advising against the peerage.
The Labour Party received more than £2.5m in donations, with that figure rising to £4.3m once other public funds are included.
The Liberal Democrats received £922,663 in donations from the public, with short money and other non-cash donations taking that amount to £1.2m overall.