A belly piercing that is still healing can close almost immediately. If it’s already healed, then it can take anywhere from a couple of weeks to several years to close. Some belly piercings may never completely close.
Simply so, will my belly button piercing close if I take it out for a day?
The only thing I suggest is if it’s a new piercing don’t take the ring out until it has healed as it’s an open wound and you can get bacteria in it and if you take the ring out before it’s healed properly you can cause an infection which will sit in the opening when it closes.