The Global Tankless Water Heater Market Size was valued at approximately USD 4.10 Billion in 2024 and is projected to grow from USD 4.53 Billion in 2025 to around USD 12.29 Billion by 2035 with a compound annual growth rate (CAGR) of 10.49% from 2025 to 2035. Growing awareness of energy efficiency, the need for continuous hot water, space-saving designs, technological improvements, and the expansion of residential and commercial building globally are the main factors propelling the tankless water heater market.