The clause, which required Valencia to pay a €500,000 signing bonus, was triggered after the 32-year-old's performances in the final months of the season proved instrumental in the club's survival.
MARCA had reported the decision was effectively made in May, and the club confirmed it officially on Thursday.
Dimitrievski's season started in the most difficult circumstances possible. Head coach Carlos Corberán had no confidence in him and attempted to move him on in the summer, eventually bringing in Athletic Club goalkeeper Julen Agirrezabala on loan as a direct competitor.
The arrangement included clauses penalising Valencia financially if Agirrezabala failed to accumulate minutes — terms that Dimitrievski found deeply humiliating and said so publicly during an international break visit to North Macedonia, accusing the club of creating unfair competition and a hostile environment.
He was required to apologise to the squad in person.
The situation transformed entirely when Agirrezabala suffered a serious long-term injury that ruled him out for approximately four months. Corberán had little choice but to turn to Dimitrievski. The keeper responded to every challenge, becoming one of Valencia's most dependable performers across the final stretch of the season and playing a significant part in ensuring they retained their top-flight status.
Despite the extension, Valencia remain active in the market for an additional goalkeeper option.