hi
If data is all the same length, do this
add a column to the right of the data column and put this formula in
=LEFT(I10,2) & "-" &MID(I10,3,4) & "-" & RIGHT(I10,2)
copy down to as far as you need.
the copy the formula column and pastespecial as values.
delete the non-dash column.

you got dashes

regards
FSt1

Re
"Marilyn" wrote:

Hello I have 3700 rows , Column A is alphanumeric e.g. BR100011. I
need to convert this so that it looks like this BR-1000-11. I tried -
format- custom- ##-####-## but it does not work. HELP please thanks