Due to a variety of beer styles and storage options for your keg, there’s no set answer to this question. Depending on who you ask or what site you read, the answer will range between 20-120 days.
There are many variables that can play a role in how quickly your kegged beer starts to alter in taste, but a general rule to keep in mind is that as soon as that keg is filled at the brewery, the “freshness clock” starts. As time goes by, your beer will slowly start to taste less and less fresh.
How Are You Dispensing Your Beer?
To give you a better idea of how long your keg will last, let’s take a look at the two most common scenarios that one would find themselves in when they tap a keg.
1. Using a Manual Pump:
Commonly found attached to the top of kegs at house parties and backyard cookouts, the manual pump — sometimes called a bronco pump or party pump — works by pumping air into the keg, pressurizing it so that it can dispense your beer. If you’ve ever poured a beer out of a keg, then you’re probably familiar with this kind of pump, as well as the problems that come along with it, such as over-pumping and excessively foamy beer.