Personally, my nose has never closed up regardless of how long I leave it out, however, my girlfriends nose piercing closed up within 5 minutes of falling out and had, at this point, had it pierced for around 4 months already. I think it is very dependant on your body and how it reacts to healing as I tend to heal slower and as a result piercings take a while to close up. Hope this was helpful! xx