Raeburn, who was born in Edinburgh and lived from 1756 to 1823, was the leading portrait painter of his time in Scotland, and is regarded as one of the most accomplished and innovative in European art of the period.
The portraits, of two young boys, have been described as among the finest of Raeburn’s work still in private hands.
They depict the two eldest sons of Sir William Forbes, 7th Baronet of Pitsligo in Aberdeenshire, a wealthy and influential banker, art collector and patron.
The paintings were commissioned in 1809–11, when the young boys were around seven-years-old.
The acceptance of the two portraits settled £631,600 of tax, and come from the Forbes of Pitsligo Collection.
Edward Harley, chairman of the Acceptance in Lieu panel, said: “These portraits were amongst the finest of the artist’s paintings still left in private hands.
“The allocation of the works to the Scottish National Gallery highlights the importance of the Acceptance in Lieu Scheme in bringing exceptional works of art into public ownership.”
Speaking of the acquisition, Christopher Baker, Director of the Scottish National Portrait Gallery, said: “Raeburn’s work has enormous appeal through its technical sophistication and the empathy with which he portrayed his subjects.
“Both these achievements are brilliantly distilled in these delightful portraits.
“We are very grateful indeed to the Acceptance in Lieu (AIL) scheme for making the transfer of the paintings to the nation possible.
“It seems especially appropriate to celebrate this, in view of the age of Raeburn’s subjects, during Scotland’s Year of Young People.”