He was invited to spring training for the 2018 season, but did not make the club and played in 25 games for Pensacola and 53 for Triple-A Louisville on the year.

[2] On January 6, 2020, Tromp signed a minor league contract with the San Francisco Giants organization.

[4][5] Tromp made his MLB debut on July 29 against the San Diego Padres and went hitless over four at bats.

[6] Tromp hit his first home run in the majors on August 2, in a 9–5 loss to the Texas Rangers.

[10] On September 21, 2021, the Atlanta Braves claimed Tromp off waivers from San Francisco, and optioned him to the Triple-A Gwinnett Stripers.

On August 6, 2022, Tromp was called up to Atlanta as a backup catcher, following an injury to Travis d'Arnaud.

[14][15] On August 13, Tromp had a three-hit, three RBI performance in his first game started for the Braves against the Miami Marlins.

[17] Tromp was recalled to the major leagues on April 9, 2023,[18] after d'Arnaud was injured in a game the previous day.