When properly stored, an opened bottle of port wine can last anywhere from a few days to a few weeks. However, it's important to note that the quality and flavor of the wine may start to deteriorate over time. To ensure the best taste and enjoyment, here are a few tips to follow: 1. Proper Storage Port lasts longer than your average wine after being opened, but it doesn't last forever. Click here to find out just how long your port will last. Port wine being stored at Taylor's. How long Port wine lasts after opening. Port wine is higher in alcohol than regular wine with alcohol levels between 19-22% ABV.. Apart from Vintage Port, the higher alcohol levels mean that Port wine can last longer than regular wine after opening.This is especially true for Tawny Port. A Port under five years old can last up to five days; one that's 10 to 15 years old lasts for about three days; and anything older than 25 years should be finished the day you open it — or within 48 hours at the very latest. o1dqXKF.