How Long Does A Keg Last Once It's Been Tapped? Story by Elias Nash • 3mo. I f you've got a keg of beer, ... also known as a party pump. With this method, you pump air into the keg from the ...

You’ve got 30 days to drink your beer once the keg is open. Replacements cost from around £30 to £40 depending on which beer you choose. They are all six litres, giving you just over 10 pints.