David Sibley’s regular column “ID Toolkit” is a popular part of every issue of BirdWatching. In our November-December 2016 issue, he offered tips for identifying Purple Finch and House Finch. For further help distinguishing these birds, please flip through this slideshow.
A reliable way to distinguish Purple Finches from House Finches, Sibley writes in our November-December 2016 issue, is to look for a slight peak or triangular crest on the head of Purple Finches. You can see this in Teri Franzen's previous photo, and on the head of the male above, photographed in Salem, Oregon, by Gary Miller.