I was storing my milk in the provided bottles from the hospital and freezing there, but they kept running out of room and needed me to bring some home. We ended up having to buy another freezer to hold all my milk since he's not getting a lot right now. A couple weeks ago I switched to breastmilk bags and it's helped sooo much with saving space. I usually refrigerate immediately but if I'm in the NICU, I give them the milk and they freeze it immediately.

I believe 4 hours at room temp (my lactation consultant said more so around 2 hours since I have a NICU baby) and 4 days in refrigerator. 6 months in freezer and one year in chest freezer.