Trim-specific — a base model and a sport trim often share a bumper but not a grille — and the first thing to change at a facelift.
Grilles are trim-level specific and change at a facelift before anything else on the front end. A car with active shutters, a front camera or a badge-mounted sensor has provisions the standard grille does not, and the retaining clips generally break on removal — order them with the grille so it sits flush rather than proud of the bumper.