How many shutter panels do I need for each window? For the most part, the the large the surface area of your window, the more shutter panels you’ll need. The optimal design is to use one panel for windows up to 26” wide, two panels for windows up to 50” wide, and four for windows up to 98” wide.Single wide panels are not as user-friendly as two separate panels. Sometimes, wide panel shutters won’t fit flush against the wall due to their size. Multiple small panels fix that.For windows that you might want to open or shut often, you’ll be better suited with multiple panels, since it’s easier to open them and they have additional support from the shutter frame when you do open and shut them.