The Frick Collection, which began staying open late on Friday nights starting in 2002, has been making some of those nights free on an occasional basis for the last five years — and noticing that the crowds tend to be younger and filled with first-time visitors. Now the collection — home to three of eight Vermeers in Manhattan, along with enough van Dycks, Rembrandts, El Grecos and Turners to stock several nice museums — plans to make its free nights a regular institution, on the first Friday of every month beginning in October.

Museum admission and gallery programs — lectures and talks, music and dance, along with open sketching in the Garden Court — will be free from 6 to 9 p.m., along with access to special exhibitions. (There won’t be a First Friday in January.)

“We have seen our evening hours events become increasingly popular for their unique combination of access and engaging programming,” Ian Wardropper, the museum’s director, said. “These nights have occurred throughout the year at various intervals, and we hope that in offering them regularly at the start of the month, they will become a beloved and well-known New York tradition.”