"Sri Lanka Standard Time (SLST) is the time zone for Sri Lanka. It is 5 hours and 30 minutes ahead of GMT/UTC (UTC+05:30).The Sri Lanka Time reverted on 15 April 2006 to match Indian Standard Time calculated from the Allahabad Observatory in India 82.5 \u00B0 longitude East of Greenwich, the reference point for GMT.The entire country shares the same time. Since 1880, Ceylon or Sri Lanka Time has varied between UTC+05:30 to UTC+06:30.In 1880, it was UTC+05:30."@en .