Ishan has represented Jharkand in the Ranji Trophy for his entire career, and in 2016, still aged only 18, he struck 273 against Delhi, which at the time was a new record for Jharkand in the competition. He has also turned out for IPL sides Gujarat Lions, Mumbai Indians, and, most recently, Sunrisers Hyderabad, for whom he hit a 47-ball 106in the 2025 edition.