He is on the books of UMF Njardvik and wears shirt number 33. His main role on the pitch is Defender.

His latest transfer saw him join Víkingur Reykjavík U19 from UMF Njardvik via Loan on 2027-02-04.

Across the Iceland Besta-deild karla 2025, Haraldur Agust Brynjarsson appeared in 16 matches and averaged 0 tackles, 0 interceptions, 0 clearances, and 0 blocked shots per game.