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 want on it. 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 aren’t as user-friendly as multiple separate panels. Sometimes, wider panels can’t fit flush against the wall because of their size. Multiple smaller panels solve that issue.For windows that you may open or shut regularly, you’re usually better suited with multi-panel shutters, since it’s easier to open them and they get additional support from the frame when you do open and close them.