The A's announced the deal Saturday.
Ziegler went 3-7 with a 3.26 ERA in 64 relief appearances with Oakland last year, when he made $410,000. He held the opposition to a .241 batting average, including .213 against right-handed hitters.
The 31-year-old right-hander has a 2.51 ERA and 18 saves in 180 relief appearances over three seasons with the A's.
Ziegler intends to use some of the money to fund his "Pastime for Patriots" not-for-profit.