The 21-year-old has extended his contract by two years and will remain part of the first-team project after establishing himself in Martín Anselmi's squad at the beginning of the season. Elche confirmed the renewal on Thursday.
Houary came through every level of Elche's academy before making his first-team debut in LaLiga. He spent the second half of last season on loan at Mirandés, where he gained valuable experience in professional football before returning to the club this summer.
Anselmi immediately showed faith in him.
Houary started Elche's first three league matches of the season and has made nine appearances for the first team overall, although his involvement has subsequently reduced. He has missed the club's last three matchday squads.
That loss of minutes has not changed Elche's view of the midfielder.
The club regards Houary as an important part of its long-term plans, with the new agreement running until June 2030 and his release clause reportedly rising to between €15m and €20m.
Anselmi has previously made his feelings clear about the player.
"I trust him a lot and I think he is young and one of the best we have at the club. We will work so that he is with us. He knows that we value him highly and that he will give us a lot."
Houary's decision to return to Elche after his Mirandés loan was an important part of his development. Despite interest in another loan move, he wanted to remain with the first team and compete for his place.
The new contract now gives the club further protection around a player it believes can develop into an important part of its future.