can i use a regular priority mail box for flat rate

At that point, USPS will likely refuse the package entirely. USPS will still know exactly what kind of box it is when you hand it over to them.

Therefore, turning it inside out isn’t going to give you much concealment in the first place. If you’ve ever looked at the inside of one of these boxes, it’s heavily marked with diagonal writing that says “Priority Mail” (or “Priority Mail Express”), anyway. “Turning the packaging inside out to conceal the Priority Mail / Priority Mail Express insignia is specific misuse that is not allowed.” While USPS allows you to turn almost every kind of box inside-out, they won’t let it fly with their own packaging it’s simply not allowed. The Postal Service Doesn’t Allow You to Turn USPS Boxes Inside Out to Reuse Them However, turning boxes inside-out only works when you’re using non-USPS branded boxes or envelopes.

As long as the boxes are still sturdy enough to be used a second time, this strategy is perfectly fine. In order to reuse packaging and cut down on waste, many shippers try to turn USPS boxes inside-out.

Can i use a regular priority mail box for flat rate