Ramandeep started his professional cricket journey by making his Twenty20 debut for Punjab in the 2016-17 Inter-State Twenty-20 Tournament on January 29, 2017. His cricketing prowess was evident from the start, leading to his List A debut on October 5, 2019, for Punjab in the 2019-20 Vijay Hazare Trophy, followed by his first-class debut in the 2019-20 Ranji Trophy on February 12, 2020.

In February 2022, he was bought by the Mumbai Indians in the auction for the 2022 Indian Premier League Tournament. Though he made only five appearances for the team in the 2022 season, his performances were notable, scoring 45 runs and taking five wickets. His high impact in the Syed Mushtaq Ali Trophy for Punjab, where he played with a striking rate of 222, further highlighted his capabilities and played a significant role in his recruitment by the Kolkata Knight Riders for the IPL 2024 season.

In the IPL 2024, Ramandeep Singh has quickly made a name for himself as a game-changer for the Kolkata Knight Riders. During the team's campaign opener against Sunrisers Hyderabad at the iconic Eden Gardens in Kolkata, Ramandeep's innings was nothing short of spectacular. Coming in at a critical juncture where Kolkata had lost four wickets for just 51 runs in eight overs, the expectations were on him to stabilize the innings.