You could do it with an array formula, but I think it would be quicker to use a
couple of helper columns.

In c1, put the truncated stuff from column B:
=left(b1,16)
and drag down

Now in d1, put this formula:
=isnumber(match(left(a1,16),c:c,0))

Then filter on on column D to show the Falses. Delete those visible rows and
delete the helper columns.



GARY wrote:

Column A is 73 characters wide and it has 23,628 rows.
Coumn B is 44 characters wide and it has 2,733 rows.

How can I eliminate the cells in Column A whose 16 left-most characters
do NOT match the 16 left-most characters in Column B?

--

Dave Peterson