Chris Noth, still otherwise known as Mr. Big from “Sex and the City” (even though the show ended in 2004), has been spotted looking at two- and three-bedroom apartments at the Sorting House.

That’s the spot at 318 W. 52nd St. where new luxury condos are being built on top of a working post office.

One unit Noth eyed was Penthouse D, a $2.89 million, three-bedroom, two-bathroom unit that measures 1,409 square feet and comes with a private roof patio.

The unit includes a foyer with closet space, a chef’s kitchen, an open living/dining area and a master suite with a walk-in closet and spa-like bathroom.

There’s also a washer/dryer and white oak flooring. Building amenities include a roof deck, gym, yoga studio, bike storage and a part-time doorman.

Robin Schneiderman of Halstead Property Development Marketing, who’s in charge of sales, declined to comment.