Unsorted dates after sorting in Excel

Question

Sometimes, even though I sort the column dates from early to late, some dates remain unsorted.  I fix it by rewriting the dates manually, but this is inefficient.

Answer 1

This looks like Excel is treating your G column as numerically formatted, rather than date formatted. Notice how each date is lined up in order as if it were a single large number?

Select your G column, hit ctrl-1 to open the format window, and select the appropriate date format.

Answer 2

Are you sure Excel understands that those values are dates?  Is your system set up to understand dd/mm/yyyy formatting?  If you put =G42+1 into Q42, does it show you a date one day after the date in G42?  Can you change the date formatting to something like dd mmm yyyy (in which the month name is spelled out)?  If you add an 17/08/2017entry to your list, does it sort before all the 2018 dates, or does it group with the other 17/08 dates?

It looks like Excel is treating those values as text strings and sorting by the first few characters (just as "agreed" sorts between "adroit" and "bakery"). 

Some parts of the world (most(?) of the English-speaking parts of the world?) use mm/dd/yyyy, and if you're in one of those parts of the world (or Excel thinks you are) it will interpret 12/08/2018 as December 8, 2018, and it will interpret 17/08/2018 as a string, because it doesn't make sense as a mm/dd/yyyy date.