How many shutter panels do I need for each window? For the most part, the larger the window, the more shutter panels you’ll need. Our recommendation is to use a single panel for windows up to 26 in. wide, two panels for windows up to 50 in. wide, and four for windows up to 98 in. wide.Single wide panels aren’t as room-friendly as multiple panels. Often, wider panels can’t fit flush against the wall because of their size. Multiple small panels fix that.For windows that you’ll open or shut often, you’re usually better off with multiple panels, since they’re easier to open and have additional support from the shutter frame when you do open and shut them.