Dev Uthani Ekadashi, also known as Prabodhini Ekadashi or Devutthana Ekadashi, occurs on the eleventh tithi of the waxing moon (Shukla Paksha) in the month of Kartika. It celebrates the waking of Lord Vishnu from Yoga Nidra, bringing the four-month ascetic period of Chaturmas to an auspicious close.
Because cosmic preservation resumes active governance with Lord Vishnu's awakening, this tithi marks the formal commencement of auspicious ceremonies, marriages (vivaha), housewarmings, and sacred rites across India after the monsoon hiatus.
Devotees observe a strict fast, perform aarti with sugarcane, water chestnuts, and seasonal fruits, and create sacred floor patterns around holy basil. Many households celebrate the ceremonial Tulsi Vivah starting from this evening through the following Purnima.