In 2016, Garbers committed to the
University of California, Berkeley. He
redshirted his first year at
California in 2017. Garbers graduated with a B.A. in Political Economy in May 2021, then went on to earn a
graduate certificate in business administration in December 2021.
2018 season In 2018, Garbers shared Cal's starting quarterback position with
Brandon McIlwain in a two-quarterback system, though Garbers started the majority of the season. In his first career start, Garbers completed 18 of 28 passes for 171 yards and two touchdowns against
BYU. Garbers led the Bears to their first victory against
USC since 2003, winning 15-14 on the road. Garbers threw for 93 yards and one touchdown and rushed for another touchdown after falling behind 0-14 in the first half. The Bears finished the
2018 season with a 7–6 record, including a loss at the
Cheez-It Bowl against the
TCU Horned Frogs. Struggling to find a rhythm on offense, the Bears' offensive efficiency ranked as the second worst among all Power Five teams. Garbers finished the season with 14 touchdowns, 10 interceptions, and 1,506 yards passing. Garbers had career highs in completions, yards passing, and touchdown passes in the
Ole Miss game with 23-of-35 passes for 357 yards with four touchdown throws. Garbers suffered a broken collarbone during the
Arizona State game that sidelined him for the next five games, four of which were losses. He returned briefly for the
USC game, but sustained a concussion close to the end of the first half. Garbers returned to lead the Bears to a 24–20 win against
Stanford in the
Big Game, the first Big Game win for Cal since 2009. Garbers ran for a 16-yard game-winning touchdown, earning praise from
Green Bay Packers quarterback and former Cal quarterback
Aaron Rodgers. This win clinched bowl eligibility for the Bears while making the Cardinal ineligible for the post-season for the first time in ten years. The Bears went to the
Redbox Bowl, where they won against the
Illinois Fighting Illini 35–20, their first bowl win since
2015. Garbers had a career best-tying 4 touchdowns and was named Offensive MVP for the game. The Bears finished the
2019 season with an 8–5 record (4–5 in Pac-12 play), with Garbers going undefeated in the seven games in which he started and finished.
2020 season Garbers entered his
redshirt junior season on the
Johnny Unitas Golden Arm Award Preseason Watch List. Due to the
COVID-19 pandemic, the Pac-12 had a seven-game Conference-only lineup for the 2020 season. However, the Bears were ultimately only able to play four games for the season due to game cancellations. Garbers started the season 0–3, losing to
UCLA,
Oregon State, and
Stanford. The Bears achieved their sole win in their last game against
Oregon on December 5, ending the season with a 1–3 record.
2021 season Garbers entered his redshirt senior season as the starting quarterback. On November 6, 2021, Garbers was declared inactive for Cal's game versus
Arizona on November 6, 2021, due to COVID-19, and the Bears were forced to postpone their game the following week for the same reason. On November 20, Garbers returned from COVID to lead the Bears to a 41–11 rout of rival
Stanford, opening the game with an 84-yard pass to tight end Trevon Clark for the longest pass in the series history. Under Garbers, the Bears set a series record 636 yards of offense, and Garbers became the first Cal quarterback to win back-to-back road games at Stanford in 99 years, since Charles Erb in 1921 and 1922.
Statistics ==Professional career==