United has lagged behind its competitors in TSA PreCheck adoption, perhaps due to the merger, but is picking up steam. Los Angeles International Airport’s (LAX) Terminal 7 now has PreCheck for qualifying United flyers (see press release).
United is added to American and Delta at LAX.
Side note: first look at the official LAX website made me think it is one of those pseudo-airport websites that tries to dupe people into thinking it is official. And loading with multiple errors in several test browsers. Sad.