Cotton (Gossypium spp.) is an important commercial fibre crop in India, yet its productivity remains below the global average. The present study assessed the impact of the High Density Planting System (HDPS) on productivity, profitability, and adoption among farmers in Mahabubabad district of Telangana during wet seasons of 2023 and 2024. Demonstrations on HDPS cotton were conducted under farmers’ field conditions and compared with existing practices. HDPS in cotton significantly improved productivity and profitability compared to farmers’ conventional practices in Mahabubabad district of Telangana. The results revealed that HDPS significantly enhanced yield by 30.90% and 35.90% over farmers’ practice during 2023 and 2024, respectively. Economic analysis indicated higher average net returns (₹1,65,512 ha⁻¹) and benefit–cost ratio (1.76) under HDPS compared to farmers’ practice (₹1,02,102 ha⁻¹ and 1.31), demonstrating its economic viability under rainfed conditions. Gap analysis revealed considerable adoption gaps in critical components such as cultivar selection, spacing, sowing time, plant protection, and post-harvest management, highlighting the need for strengthened extension interventions. Notably, 56.64% of farmers exhibited a high level of knowledge, while 49.16% demonstrated high adoption of HDPS practices, indicating the positive impact of demonstrations and capacity-building efforts by Krishi Vigyan Kendras and the Department of Agriculture. The study demonstrates that HDPS is a viable and resource-efficient technology for enhancing cotton productivity and income under rainfed conditions. Strengthening extension services, ensuring timely input availability, and promoting mechanization are essential to improve its wider adoption.