Try the following: -
DateTime dt1 = DateTime.ParseExact("2013-01-14 21:09:06 PST".Replace("PST", "+2"), "yyyy-mm-dd HH:mm z", culture); DateTime dt2 = DateTime.ParseExact("2013-01-14 21:09:06 PDT".Replace("PDT", "+2"), "yyyy-mm-dd HH:mm z", culture); DateTime dt3 = DateTime.ParseExact("2013-01-14 21:09:06 PLT".Replace("PLT", "+2"), "yyyy-mm-dd HH:mm z", culture);
source share