2013
Friday, 19 July 2013
In 2013 the tithi runs from 4:42 pm on 18 Jul to 2:00 pm on 19 Jul; it is running at sunrise (the usual rule, called udaya tithi) on Friday, 19 July 2013, so that is the day of Devshayani Ekadashi.
2014
Tuesday, 8 July 2014
In 2014 the tithi runs from 5:57 am on 8 Jul to 4:40 am on 9 Jul, and it never reaches sunrise (the usual rule, called udaya tithi), so the day on which it begins is taken: Tuesday, 8 July 2014.
How the date is fixed
Devshayani Ekadashi falls on the eleventh day of the bright half of the lunar month Ashadha (Shukla Ekadashi). The date is the day on which that tithi is running at sunrise (the usual rule, called udaya tithi).
About
Devshayani Ekadashi is the eleventh tithi of the bright half of Ashadha, in June or July. The Puranas describe Vishnu retiring to rest on this day and waking on Devutthana Ekadashi in Kartika; the four lunar months between are chaturmasa, during which weddings and other samskaras are traditionally not held. The Ekadashi rule applies: the tithi must be present at sunrise, and the Vaishnava and smarta calendars can differ by a day. In Maharashtra the Pandharpur wari of the Varkari pilgrims ends on this day.
How it is observed
The Ekadashi fast, Vishnu worship, and the taking of chaturmasa vows that run until Kartika.