At age 15, he accepted an apprenticeship position with the SC Rapperswil-Jona Lakers, a National A League team in Switzerland, where he observed and learned from David Aebischer and Jason Spezza.

After completing the 2012–13 season in his native Switzerland with the U17 SC Rapperswil-Jona Lakers, Meier was selected 12th overall by the Halifax Mooseheads in the 2013 Canadian Hockey League Import Draft.

[3] At age 15, Meier accepted an apprenticeship position with the SC Rapperswil-Jona Lakers, a National A League team in Switzerland, where he observed and learned from David Aebischer and Jason Spezza.

[1] His play with the Lakers earned him international attention and he was selected 12th overall by the Halifax Mooseheads in the 2013 Canadian Hockey League (CHL) Import Draft.

[7] His career-best 44 goals and 46 assists for 90 points through 61 games,[1] earned him significant attention from hockey scouts leading up to the 2015 NHL Entry Draft.

[14] Despite impressing the Sharks' coaching staff during training camp, an illness held off Meier's NHL debut for the start of the 2016–17 season.

[16] After missing nearly a month due to mononucleosis, Meier was assigned to the Sharks' American Hockey League (AHL) affiliate, the San Jose Barracuda, on 26 October 2016.

[20] During the 4–2 win, Meier played alongside Joonas Donskoi and Chris Tierney as he scored his first career NHL goal against Carey Price in the first period.

[24][25] After the Sharks finished the season in third place in the Pacific Division,[26] Meier competed in five games against the Edmonton Oilers during the 2017 Stanley Cup playoffs.

[29] In November 2017, Meier was fined $2,403.67 for striking Vancouver Canucks defenceman Michael Del Zotto in the face with his stick during San Jose's 5–0 win.

[29] Once the Sharks were eliminated, Meier joined Switzerland men's national ice hockey team at the 2018 IIHF World Championship.

As a result of the acquisition of Erik Karlsson during the off-season, and his impressive play during the 2017–18 season, Meier began the campaign on the Sharks' second line alongside Logan Couture and Tomáš Hertl.

[37] Meier's production helped the Sharks maintain an 18–11–5 record to tie them for second place in the Pacific Division behind the Calgary Flames by mid-December.

[41] Following the departure of Joe Pavelski during the 2019–20 offseason, Meier was expected to replace him on the Sharks' first power-play unit and become a bigger presence on the penalty kill.

[44] The Sharks opened the season with four straight losses before winning three consecutive contests as Meier played in his 200th NHL game on 16 October.

[47] When the NHL resumed for their shortened 2020–21 season, Meier began playing on the Sharks' second line as a winger for Ryan Donato and Tomáš Hertl.

[48] Due to the shortened season, the Sharks began by playing eight road games over 15 days and their poor performance placed them last in the Honda West Division by early February.

[51] Shortly after ending their win streak, Meier and teammate Kevin Labanc were placed on the NHL's COVID-19 protocol list on 2 November.

As a pending restricted free agent at the conclusion of the season, Meier signed an eight-year, $70.4 million contract extension with the Devils on 28 June 2023.