Coconut milk can last up to several weeks if stored properly in the fridge if opened. When stored this way, it will generally remain good for 2-3 weeks, depending on the brand and how fresh it was when purchased. You'll know it has gone bad when its texture changes; if the liquid is thin or separated, it’s spoiled and no longer safe to use. If you want to keep your coconut milk longer than 3 weeks out of the fridge, one option is to freeze it in an airtight container or resealable plastic bag where you can store it for up to 6 months without losing quality or taste. When still unopened, It's important to note that coconut milk should always be kept in an airtight container and away from direct sunlight, heat, and humidity. The best way to store it is on a shelf in your pantry at room temperature.