A Police Scotland spokesman for the Highlands and Islands division said: “The body is believed to be that of missing man Blair James Davidson who was last seen in the vicinity of the Kessock Bridge on 28 December 2012.
“Formal identification, however, will require to be carried out.”
He added that the 18-year-old’s family had been informed.”
The body was found on the shore in the North Kessock area at around 3.30pm on Thursday.
Mr Davidson’s red Renault Clio was found abandoned on the A9 Inverness to Thurso road at Kessock Bridge by police officers on patrol at around 4.30am on 28 December.
Extensive air, land and sea searches were carried out, but there was no sign of him.
Mr Davidson was a fomer pupil of Inverness Royal Academy and grew up in the city’s Hilton area.