In his first season, Leicester finished as champions on odds of 5,000–1, making Fuchs the first Austrian to receive a Premier League winners’ medal since Arsenal’s Alex Manninger in 1998. Following the insertion of Fuchs into the lineup on Matchday 8, Leicester City led the Premier League in clean sheets along with Arsenal, with 15. Fuchs himself led the league during this period in successful tackles with 77, while finishing second in interceptions with 98.

Fuchs made his debut for Austria on 23 May 2006 in a friendly match against Croatia, replacing Stefan Lexa for the final six minutes of the 1–4 loss at the Ernst-Happel-Stadion in Vienna.

Prior to UEFA Euro 2008, he joined the German side VfL Bochum. He later described it as a useful move to play regularly while attracting attention from bigger teams. In 2010, he was signed on loan by 1. FSV Mainz 05, a newly promoted team who ended the season in the top five.

On 11 August 2010, in the absence of regular skipper Marc Janko, Fuchs captained his nation for the first time in a 0–1 friendly loss to the Swiss in Klagenfurt. That 17 November, he scored his first international goal, equalising in a 1–2 home friendly loss to Greece.

On 6 June 2011, Fuchs signed a contract until 30 June 2015 with Schalke 04. The transfer fee is reportedly undisclosed by Schalke’s sport and communications manager Horst Heldt. Fuchs was assigned the number 23 shirt, previously worn by Danilo Fernando Avelar.

Fuchs received the armband on a permanent basis at the behest of manager Marcel Koller on 13 August 2012. He played all 10 games as they qualified for UEFA Euro 2016, the first time they did so, and featured in every minute of the group stage elimination in France. Afterwards, he retired from international play with a total of 78 caps, declaring “I am very proud of the 10 years that I have spent with the national team. I did everything with passion and, as I said, I am very, very proud.”

On 3 June 2015, Leicester City announced the signing of Fuchs on a free transfer, signing a three-year deal with the Foxes effective from 1 July. Signed under previous manager Nigel Pearson, Fuchs didn’t have a regular spot in new manager Claudio Ranieri’s squad until October. Fuchs made an appearance in Leicester’s third round League Cup tie against West Ham United, providing an assist for Andy King’s extra time winner. Following a 2–5 loss to Arsenal on 26 September, Ranieri elected to shake up his defensive back four, inserting Fuchs and teammate Danny Simpson in place of Jeffrey Schlupp and Ritchie De Laet, respectively. Fuchs made his first Premier League start the next week against Norwich.

Prior to signing for Leicester, Fuchs had an offer to play in the United States, where his family live, but he turned it down for financial reasons. He said in March 2016 “My intention is to play in the US. I have come [to Leicester] for three years. I decided that I would sign one last contract in Europe, when I left Schalke, then go to the US.”

On 21 October 2016, Fuchs signed a new contract with Leicester, keeping him with the club until June 2019. The next day, Fuchs scored his first goal for Leicester against Crystal Palace, volleying home a corner-kick clearance by Christian Benteke for the team’s final goal in a 3–1 victory.

In May 2019 he signed a new one-year contract with Leicester.