The 17-year-old, who made his La Liga debut last season under Marcelino, has extended his deal by two years, having previously been contracted to the Yellow Submarine until 2029.
Maciá earned the renewal after a breakout 2025-26 campaign in which he rose quickly to prominence with Villarreal B, starring for a side that defied expectations to reach the promotion play-offs for Segunda División.
His quality and reading of the game did not go unnoticed by the first team either, with the Elche-born midfielder handed five appearances in La Liga and one in the Copa del Rey under Marcelino last season.
He is now involved in first-team pre-season training under new head coach Iñigo Pérez, having already featured in a friendly against Benfica and hoping to add further minutes when Villarreal face PSV Eindhoven this Saturday.
The renewal underlines Villarreal's continued faith in their academy system, in a season in which the club's youth talent is expected to play a prominent role within the first-team picture.
Maciá has risen quickly through Villarreal's ranks since joining from Elche, progressing through the club's junior sides before being fast-tracked into Villarreal B under coach David Albelda without needing to pass through the usual intermediate levels. His performances in Primera Federación caught the eye of Marcelino during last season, while his composure on the ball and tactical intelligence have also seen him called up to represent Spain's youth national teams.
With Villarreal keen to build around home-grown talent this season, Maciá's new deal is being viewed at the club as a statement of intent, tying down one of their most promising prospects for the long term just as he prepares to make the step up to regular first-team involvement. His progress will continue to be closely watched by Iñigo Pérez's coaching staff as pre-season continues.