Mortgage Beer Share definition Flag A nickname for cheap beer, like Natural Light, or Keystone. Cheap beer one resorts to buying when they have a mortgage. Not anymore, now I drink mortgage beer.Mortgage beer?Natty Light.Ah, gotcha Mortgage Beer by Luke5119 October 10, 2015 0 0 Get merch Get the Mortgage Beer mug. Buy Now — $32.95 See more merch