Harvard has a secret back door for ultra-rich kids with lousy grades

What does Harvard University do when faced with well-connected applicants — the children of mega-donors or other highly influential people — who have less-than-ideal SAT scores and GPAs?

The put them on the Z-List, according to a college admissions coach.

That means the students are advised to matriculate after taking a gap year, making them so-called “data ghosts” — meaning their lackluster academic statistics are not reported in the incoming freshman class.

That way Harvard doesn’t take a hit to its stellar academic averages — or institutional rankings.

“If Harvard doesn’t want the student hurting their US News and World Report ranking with their GPA and test scores, they admit them through the Z list,” Brian Taylor, managing partner of Manhattan-based college admissions firm Ivy Coach, told The Post. (While Harvard’s Law and Medical Schools both pulled out of US News and World Report’s college rankings, the university at large has not.)