here's one way: insert a helper column next to your column of acct. numbers.

Assuming your data begins in J1, in K1 place this formula:

=IF(J1<100,J1*10,J1) and copy down your range. (now all cells will be a 3
digit number)

Next, highlight the entire range and SortAscending by column K

Finally, delete column K

Your original values are now sorted in your desired order.

HTH
__________________
Bruce