Leroy Fer completed his transfer to Norwich City on Saturday 13th July 2013, signing from FC Twente on a four-year deal for an undisclosed fee

Fer began his career at the local Zoetermeer club DWO. In his first full season, Fer's team won friendly matches against youth teams from professional sides, like Sparta Rotterdam and Feyenoord. However, Fer stayed at DWO until the age of nine before joining Feyernoord's youth setup.

Fer had his breakthrough in Feyenoord's first team in the season 2007–08. On 2nd December 2007, Fer made his official debut for Feyenoord under the management of Bert van Marwijk. Four days later he signed his first professional contract. On 30th March 2008, Fer scored his first Eredivisie goal in the away match against NAC Breda. He won the Dutch Cup with Feyernoord that season.

In the 2008/9 season, he became a first team regular and attracted the attention of a number of clubs including Juventus. He later became vice-captain of the club

Fer joined fellow Eredivisie club FC Twente at the end of August 2011 in a deal reported to be worth €5 million. Fer played 71 times for the club, scoring 21 goals over the next two seasons.

On 28th January 2013 it was announced that Everton had agreed a deal, reportedly worth £8.6 million, to sign Fer. The deal fell through when a medical revealed the player had a long term knee injury and Everton wanted to neotiate a payment by appearances fee

Fer has also captained the Holland Under-17s whose side reached the European Championships in 2007. He later played for the Under-19s and Under-21s and at the time of signing for Norwich, has two full caps for Holland.

Fer has various nicknames. In his youth he got nicknamed De Uitsmijter (The Bouncer) by Feyenoord youth coach Jean-Paul van Gastel for his strong physical appearance. Other nicknames are Lerra and Ferovic. Cor Pot, coach of the Netherlands U21, compared Fer with Patrick Vieira. According to Pot both players show many similarities, on and off the field

Suspended for the opening game of the 2013/14 season, Fer made his first start for Norwich on 24th August 2013 in a 1-0 defeat away at Hull City Tigers. He scored his first Norwich goal in the 6-3 Capital One Cup second round victory over Bury on 27th August 2013.

He made 32 appearances, scoring four goals in the 2013/14 season in which Norwich were relegated from the Premier League.

Fer was included in Holland's World Cup squad for the tournament in Brazil in June/July 2014. He became the first Norwich City player to score in a World Cup finals when he netted Holland's opener in their final group game against Chile which Holland won 2-0. Fer played no further part in the World Cup as Holland reached the semi-finals before being defeated by Argentina on penalties.

Following his return to England, Fer was linked with moves to AC Milan, Seville and to QPR who were reported to have bid 6milion euros. Fer made one appearance for Norwich in the Championship, coming on as substitute in the 3-0 home win over Watford on 16th August 2014 before completing a £8m move to QPR on 20th August 2014, a fee that is Norwich's record sale. Fer signed a three year contract with QPR saying "It was always my dream to stay in England, in the Premier League. QPR did well last season to come up and the squad is full of top players, so I'm delighted to be here. I'm just looking forward to showing what I'm capable of here at QPR."

QPR manager Harry Redknapp said "Leroy has all the attributes you'd be looking for from a central midfielder. He's just an outstanding midfield player - great hysique, fine ability, and he gets box-to-box." Fer made his QPR debut in the 4-0 defeat to Tottenham on 24th August 2014.

Despite claims that Rangers were better equipped to avoid relegation than Norwich, Fer suffered his second successive relegation when QPR were relegated tot eh Championship following a 6-0 defeat to Manchester City. He was linked with moves to Seville and West Ham but travelled to Sunderland on 5th August 2015 to join the Black Cats on a season long loan only to fail his medical.

On 1st February 2016, Fer joined Swansea on loan for the remainder of the 2015/16 season. He made 19 appearances for the Championship club during 2015/16. He made 11 appearances for the Swans.

On 5th July 2016, he became Swansea's first signing of the summer, joining on a three year contract.

Fer experienced his third relegation from the Premier League at the end of the 2017/18 season as Swansea finished eighteenth in the Premier League.

On 29th January 2019, he was linked with mvoes to French side Lille and Turkish side Fenerbahce and then with Aston Villa the following month. Fer was released by Swansea on 8th May 2019 to cut costs following their failure to return to the Premier League. Also departing were Wilfred Bony, Dutch winger Luciano Narsingh and defender Martin Olsson. Fer scored 10 goals in 101 appearances since joining Swansea

On 25th July 2019 he signed a one year deal with Feyernoord. He said "My heart is here. I'm very happy to be back. I feel stronger and fitter and I will do everything in my power to get back to my old level as soon as possible, in order to have a great season with Feyenoord."

On 24th Auguist 2021 he moved to Turkish Super Lig side Alanyaspor on a two year contract.