The Liberal Party's grovelling apology to Lucy Turnbull has cost much more than just embarrassment.

The party has handed over a cheque for $40,000 to the St Vincent de Paul Society, the proceeds of two exclusive fundraisers at which the Prime Minister's wife was the star attraction.

As revealed by Fairfax Media last week, the party inappropriately used Ms Turnbull's position as the head of a NSW government planning body, the Greater Sydney Commission, to promote a $3000-a-head women-only boardroom lunch hosted by Senator Michaelia Cash.