The most successful strategy for freezing peach cobbler depends on the type of pastry that tops the fruit filling. Leavened doughs, such as the biscuit-like topping used on traditional cobblers, should be baked before you freeze them. Freezer storage can interrupt the chemical processes that make that type of pastry light and fluffy. Unleavened pastries, such as toppings made out of pie crust, can be frozen before or after baking. Do not freeze any kind of crumb topping, like streusel, regardless of whether or not you have baked it yet. Crumb toppings are usually too delicate to withstand freezing and thawing.
Exceptions to the freezing guidelines for biscuit-like dough and crumb toppings do not apply to recipes that explicitly state they are freezer-safe. If you have frozen the same crumb topping or unbaked biscuit-like topping with success in the past, feel free to freeze your peach cobbler after any stage of preparation.
Freeze all food at or below 0 degrees Fahrenheit. Remove all plastic packaging materials before you reheat or bake cobbler in an oven. Add extra seasoning or a crumb topping when the cobbler has about 15 minutes of reheating or baking to go.