Hailing from Jalandhar, Punjab, Harnoor first rose to prominence as a key member of India’s U19 World Cup-winning squad in 2022, where he scored 197 runs, including a gritty 46 in the final against England, helping India clinch their fifth title. A left-handed batter, Harnoor made his first-class debut for Chandigarh in the 2022-23 Ranji Trophy against Baroda, scoring a composed 46, and debuted in T20s during the 2023-24 Syed Mushtaq Ali Trophy (SMAT). For his ability to time the ball, Harnoor was bought by the Punjab Kings in IPL 2025 for INR 30 lakhs. IPL presents him with the opportunity to share the dressing room with the likes of captain Shreyas Iyer, Marcus Stoinis and Head Coach Ricky Ponting and further sharpen his skills.