The couple from Largs, who donated £1m of their EuroMillions win to the SNP to help its drive for independence, attended the event at the Thistle Hotel in Glasgow’s city centre on Friday night.
Colin, 64, stood as a candidate for the party in 1987. The couple’s record gift makes the SNP the third-richest political party in the UK.
However, Colin Weir said the donation was about “more than party politics”.
“We want to give the people of Scotland a fair chance in the referendum campaign. That’s why we are supporting the SNP now and into the independence referendum,” he said. “The only people with the right to decide Scotland’s future are the people of Scotland themselves, and we want to support the SNP and the referendum campaign in helping Scotland make that decision fairly.”
The couple – now the 21st-richest people in Scotland – have recently moved to a new £850,000 home.