[1] He completed the Grandmaster requirements on 18 September 2008 during the European U16 championship, when his rating reached 2500, the title confirmed by FIDE in 2009.

[6] In 2015, Ter-Sahakyan won the Students section of the Moscow Open with 6/9, half a point ahead of Daniil Dubov and finished third on tiebreak with 7/9 at the Karen Asrian Memorial.

[7][8][9] In 2018, Samvel Ter-Sahakyan was a key player for the Armenian Eagles, who won the ProChess League championship in San Francisco, USA.

At the 44th Chess Olympiad, held in Chennai, India, in 2022, Samvel was a member of the Armenian national team, that secured the silver medal.

In 2024 Samvel was a team member of AX Gaia, which won all nine matches, successfully defended their title and claimed victory in the Portuguese League, held in Soure, Portugal .