The A's announced the deal Saturday.
Lowrie, who turns 38 next month, returned to Oakland last season on a minor league contract and became a key contributor on a club that missed the playoffs after three straight berths.
He batted .245 with 28 doubles, 14 home runs and 69 RBIs over 139 games. His 449 games at second base are fifth most in Oakland history.
Speaking Sunday, Lowrie said he can't predict how long it will take to restore his timing, and adjust to the adrenaline rush of the MLB level, noting that there's a reason spring training is usually six weeks.
"I have to take it day-by-day, and build up,'' Lowrie said. "Because if you look at the pandemic year (2020) ... you look at the number of injuries that happened after that. That's why we have this build up in spring training, to protect guys over the course of a season."
A career .260 hitter with a .745 OPS, Lowrie batted .245 with a .717 OPS in 139 games last season, including hitting left-handed only the last month because of the hand fracture. He finished second on the club with 28 doubles.
"Jed's always had a good discipline for the strike zone,'' A's manager Mark Kotsay said. ``He has consistent contact, a consistent barrel, and his approach: he's a professional hitter. So all these hitters that are here will benefit from him being around and talking hitting.''
Earlier in the week, the A's brought back fan favorite veteran catcher Stephen Vogt.
Information from The Associated Press was used in this report.