Guruvara Ekadasi Vrat (Ekadasi which falls on Thursday) is highly auspicious Ekadasi vrat. Observing Guruvar Ekadasi is considered highly meritorious as Thursday or Guruvaram is the most favorite day for Lord Vishnu.
Ekadasi vrat, most common vrat dedicated to Lord Vishnu, is observed on 11th day in Shukla and Krishna Paksha of a Hindu month.
Shanivar Ekadasi (Ekadasi falls on Saturday) is also considered auspicious.
Strict fasting is observed on Ekadasi day in some Hindu communities. Vishnu Sahasranama Stotram, Vishnu Suktam and Sri Ranganatha Ashtakam are the most popular Stotrams or prayers to chant during Vishnu Puja on Ekadasi.
In 2012, Guruvara Ekadasi is observed four times: twice in January 2012 and twice in October 2012.
January 5, 2012: Vaikunta Ekadasi / Mukkoti Ekadashi / Putrada Ekadasi
January 19, 2012: Shattila Ekadasi
October 11, 2012: Indira Ekadasi
October 25, 2012: Pasankusa Ekadasi / Padmanabha Ekadashi / Papankusha Ekadasi